The best drain blasters, compared.
Top pick: Rothenberger RoPump 71991 – Highest score at 86: 4.3 from 5,304 reviews, 50 psi stated, for a light sink, bath or shower. Not a WC. Best value: XREXS drain buster, two cups – About £12.34, 4.0 from 3,987. A stroked dual cup. The gun at about £8.99 has nine UK reviews in the saved listing. Updated 22.10.2026.
A drain blaster stores compressed air and releases it through a rubber adaptor, so you can shift a slow basin, sink, bath, shower or WC without a corrosive cleaner. In a UK home the usual choices are a stored-air gun with a pump and a trigger, a suction-pressure force pump you stroke by hand, and a dual-cup plunger. What decides the fit is the cup against the waste. English Approved Document H gives minimum trap sizes: a washbasin at 32 mm, a bath, shower or sink at 40 mm, and a WC outlet at 75 mm or 100 mm. A large WC cup will not seal a shower tray, and a small bell will miss a recessed kitchen waste. Keep the first charge low on plastic and push-fit joints. A pressure figure only helps when the units agree. Traps should keep at least a 25 mm water seal. Scotland and Northern Ireland use their own building rules. Matching the mechanism to the waste is set out in the [drain blaster buying guide](/hub/diy-supplies/drain-blaster/sub/drain-blaster-buying-guide).
A drain blaster stores compressed air and releases it through a rubber adaptor, so you can shift a slow basin, sink, bath, shower or WC without a corrosive cleaner.
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Personal buying guide
Question 1 of 2
What are you trying to clear?
Across 5,304 amazon.co.uk reviews rated 4.3, the Rothenberger RoPump 71991 is a 360 g suction-pressure hand pump that buyers use on a slow kitchen sink, a soap-gummed bathroom waste, and a shower or bath. The listing states a maximum of 50 psi, a 440 mm wand, a triple sealing lip, CE, and a two-year manufacturer warranty, and it does not list a toilet among the outlets. One UK reviewer put the bell at about 95 mm and could not seal a recessed kitchen waste until a smaller cup was taped on. An older review found the head too small and too hard for some UK kitchen sinks. A couple of pumps cleared a blockage after other attempts, though a heavy clog can push mess back into the bowl. The stroke takes practice. This is a force pump you work by hand, not a stored-air trigger gun, and at about £21.92 it is the top pick here for a light sink, bath, or shower blockage.
Pros
Cons
Best for: A light blockage in a sink, bath, or shower, when you will stroke a force pump and the bell can cover the waste.
Less suitable: A toilet, or a recessed kitchen waste the bell will not seal.
Specifications
Common questions
Is the RoPump a trigger drain blaster?
The listing describes a suction-pressure hand pump with a ball joint and a triple-lip bell. It does not describe a stored-air trigger.
Will it fit a toilet?
Toilets are not in the listed outlets. The outlets named are sinks, urinals, showers and bathtubs.
What pressure does the listing state?
The amazon.co.uk line states a maximum of 50 pounds per square inch, and the specification field says CE.
The HzNzYHD at about £14.99 is a stored-air gun you charge by pulling the handle about 10 to 20 times, then blast, rather than plunging in place. Across 536 reviews at 4.2, the first 50 in the saved listing are marked United Kingdom. Those reviews include a kitchen sink that stayed clearer than after a chemical cleaner, a shower tray in a couple of blasts, and a toilet, including one case of baby wipes cleared in two blasts. The listing says about 12 times atmospheric pressure and “12 typhoon wind speed”, and there is no test report behind either line. Item weight is 650 g while a bullet says 750 g. One buyer pumped until their shoulders hurt and the sink stayed blocked, and another said some modern sinks need a larger cup. The gun is short, so a review tells you to stand back if the WC is over half full, and one parcel arrived with three ends rather than four.
Pros
Cons
Best for: A sink, shower tray, or WC when you want a trigger gun with a few hundred UK-marked reviews and will stop if the cup will not seal.
Less suitable: A modern sink that needs a larger cup, or a job you expect one short pump to finish.
Specifications
Common questions
How do you charge it?
The listing says pull the handle about 10 to 20 times and repeat until the blockage moves. There is no pressure gauge.
What does the listing say it will not clear?
The bullet says it is not for urine scale, cement or a hard object.
Why are there two weights?
The bullet says 750 g. The item-weight field says 650 g. Both are printed. Neither is corrected here.
The LSDZHK at about £14.99 is a 650 g stored-air trigger gun with adaptors stated at 1.5 cm, 3.5 cm, 11 cm, and 11.5 cm, charged by 12 to 15 pumps before the trigger. Across 118 reviews at 4.2, 32 are marked United Kingdom. Those UK texts include a long-standing blockage moved in a few pumps, a bath waste cleared on the first try when a plunger had not, and a toilet that liquid unblockers had left blocked. Splash is the limit that keeps returning: water crossed the room when the cover was off or the seal missed the U-bend. A handle arrived snapped, and other buyers reported little force or still called a plumber. The package-quantity field says 2 while the included-components line says one air pump, so the page does not settle how many guns are in the box. There is no bar figure, only the words high pressure.
Pros
Cons
Best for: A bath waste or a WC when you will use the splash cover and an 11 cm adaptor actually seats.
Less suitable: A shower tray the bullets do not name, or a box you need to trust to arrive with an intact handle.
Specifications
Common questions
What adaptor sizes are printed?
The bullet lists 1.5 cm, 3.5 cm, 11 cm and 11.5 cm.
Does the box include a splash cover?
The specification line says Air Pump. UK reviews in the saved listing mention a polythene splash guard. The guard is not named in the specification.
How many units are in the package?
Item package quantity is 2. Included components say Air Pump. The count of complete guns is not stated
The Lichll at about £11.99 is a stored-air trigger gun with four suckers stated at 5 cm, 6 cm, 11.5 cm, and 20.5 cm, the widest cup printed in this set. The star line is 4.1 from 53 reviews, and only eight of the printed reviews are marked United Kingdom. One of those cleared sinks and a toilet. Another buyer could not get the described action because the box had no instructions and the online ones lacked detail. Item weight is 816 g and a bullet says 1.86 lb, about 844 g, so the two masses do not match. There is no psi or bar figure, only the words high pressure. At least two buyers reported no result, and a 4.1 on eight UK texts is a thin base for a gun you will point at a pan.
Pros
Cons
Best for: A sink or WC when you need a stated 20.5 cm sucker and you can work out the action without a useful leaflet.
Less suitable: You want a large UK review sample, or a single stated weight.
Specifications
Common questions
What sucker sizes are printed?
The bullet lists 5 cm, 6 cm, 11.5 cm and 20.5 cm.
Does the listing include a shower?
Yes. Shower, bathtub, sink, washbasin, toilet and floor drain are named.
Which weight should you use?
The item-weight field says 816 g. The bullet says 1.86 lb. Both stay as printed.
The XREXS at about £12.34 is a 400 g dual-cup plunger, with a 15 cm cup stated for toilets and urinals and a 6.3 cm cup stated for a kitchen sink or bathtub. Across 3,987 amazon.co.uk reviews at 4.0, UK buyers report repeated toilet clears and a shower tray that moved in two pumps when the overflow was blocked. The listing describes a vacuum pipe and two suction cups, and it does not mention a trigger, a stored-air cylinder, or a pressure figure. The seal on a plughole needs hard downward pressure, and one review found the cup too soft and shallow for a firm blockage. A shaft seized so the handle would barely move, and another account reports rust and breakage in under a year. On a toilet the fit can be awkward, and the bowl contents can be drawn upward. It is the best value in this set when you will stroke a cup, and the wrong tool if you came for a trigger gun.
Pros
Cons
Best for: A basin and a WC when you will stroke the 6.3 cm or 15 cm cup and block the overflow.
Less suitable: You want a trigger and a stored-air charge.
Specifications
Common questions
Does it have a trigger?
The listing describes a vacuum pipe and two suction cups. It does not mention a trigger or a stored-air cylinder.
Which cup is for a toilet?
The listing says the 15 cm cup is for toilets, squats and urinals, and the 6.3 cm cup is for a kitchen sink or bathtub.
Is a shower mentioned?
A bathtub is named for the small cup. A shower tray is not in the bullet list. UK reviews in the saved listing include a shower-tray clear.
The XMPEKO at about £14.99 is a 680 g stored-air trigger gun with four suckers, and the listing tells you to inflate 12 to 15 times before you pull the trigger. Across 662 reviews at 4.0, the first 50 in the saved listing are marked United Kingdom, and those buyers cleared a toilet on a second, third, or fifth attempt and a kitchen sink on a sixth, including after a traditional plunger had failed. The same page claims about 12 times atmospheric pressure with no test in the saved listing. One review cites instructions of 40 pumps, and that buyer managed about 10. Pressure leaked at the joints after a few months, so a later charge would not hold, and the paper instructions were unclear until the buyer watched videos. It often needs several attempts. At the same shelf price as the HzNzYHD it has more reviews and a slightly lower star line, and neither number is a lab rank.
Pros
Cons
Best for: A toilet or kitchen sink when you can repeat the shot and accept that the stated pump count may be more than you can manage.
Less suitable: You need the gun to hold pressure for months, or you want a measured pressure rather than a 12-times bullet.
Specifications
Common questions
How many pumps does the listing ask for?
The bullet says inflate the cylinder 12 to 15 times, then pull the trigger. One UK review cites different instructions of about 40 pumps.
Is the 12-times-pressure line a test?
The listing says about 12 times atmospheric pressure. No test report is in the saved listing.
Which wastes are named?
Toilet, washbasin, bathtub, shower, sink, squatting pan, floor drain and a kitchen pipe.
The inShareplus kit at about £22.99 weighs 1.01 kg and combines a foot-operated pump, a pressure gauge, a button release, four heads, and a glove. Across 160 reviews at 4.0, the first 50 in the saved listing are marked United Kingdom, and buyers report a shower drain cleared in one blast and an upstairs toilet cleared on modest pressure. The listing prints 8 bar (8 PSI) beside bands of 2–3 bar, 4–6 bar, and 7–8 bar, and 8 bar is not 8 psi, so you cannot treat the gauge as a checked scale. One toilet attempt failed and splashed sewage, a unit stopped holding air the same day, and two parts were missing from a box. A cheap traditional plunger worked when this kit did not, in one review. It is the only gauge in the set, and the clashing units are why that gauge does not make it the top pick.
Pros
Cons
Best for: A shower or an upstairs WC when you want several heads and you will not quote the conflicting bar and psi line.
Less suitable: You need a pressure figure you can quote, or a kit that arrived complete and held air.
Specifications
Common questions
What maximum pressure does the listing state?
One bullet says 8 bar (8 PSI). The same listing also suggests 2–3 bar, 4–6 bar and 7–8 bar. Those units are not reconciled here.
Does it include a gauge?
Yes. The listing describes a pressure gauge on top and a foot-operated pump base.
Is every toilet shape confirmed?
Toilets are named. A question about all types of toilets is in the saved listing and is not answered as yes.
The JJX at about £8.99 is the cheapest stored-air gun in this set, at 649 g, with cups stated from 5 cm to 11.5 cm and no pressure figure. The star line is 3.9 from 135 reviews, and only nine in the saved listing are marked United Kingdom. Short UK texts say it worked and avoided a plumber, and they also report splash, a result only some of the time, and a leaflet with pictures but no assembly or use instructions. One UK review says too high a first release on sink pipework can force joints apart, and that you should raise the charge in steps. Length and width are not on the page. The about £8.99 shelf price is why it looks like the bargain, and those nine UK reviews are why it is not the best value here.
Pros
Cons
Best for: A low-cost trial on your own drain, if you raise the charge in steps and accept splash.
Less suitable: Push-fit sink joints on a full first charge, or a decision based on more than nine UK reviews.
Specifications
Common questions
What cup range is printed?
The bullet says four sizes from 5 cm to 11.5 cm, also written as 2 to 4.5 inch.
Is a shower named in the outlet list?
The printed outlets are toilet, floor drain, sink, bathtub, squatting pan and blocked pipe. A shower question is in the saved listing and is not given a separate yes.
Are the 135 reviews all from the UK?
The saved listing marks 9 reviews as United Kingdom. The rest shown are other marketplaces. The 3.9 is the amazon.co.uk headline figure.
The YWHWLX at about £9.48 is a 620 g stored-air trigger gun with four suckers whose diameters are not stated, plus a splash-proof plastic film. The star line is 3.7 from 90 reviews, and only one review in the saved listing is marked United Kingdom, a short line that the job was done. The other printed texts are from Canada or the United States, and those themes include no useful charge, cups that did not fit the holes, and returns. The listing says cover the opening with the film and leave a gap for the plunger. There is no bar or psi figure. The price is low, and the UK opinion you can actually read is one sentence.
Pros
Cons
Best for: A buyer who wants the splash film and will judge the gun from the packet, not from the 3.7.
Less suitable: You want cup diameters, or a UK review sample larger than one sentence.
Specifications
Common questions
Does the box include a splash film?
Yes. The bullet tells you to cover the opening with a plastic film and leave a gap for the plunger.
Are cup diameters stated?
Four suckers are included. Diameters are not stated
How many of the printed reviews are from the UK?
The saved listing marks one review as United Kingdom. The headline is 3.7 from 90 on amazon.co.uk.
The 1ABOVE at about £11.99 is a 520 g air-pressure unblocker with a large head and a small head, and the listing states neither a pressure figure nor a material. Across 51 reviews at 3.4, 16 are marked United Kingdom. One of those cleared a shower on the first blast, and buyers who got a seal describe a strong shot. The same UK reviews is dominated by units that would not hold pressure, leaked air, or would not compress from new. The rubber would not seal a square toilet or the bowl, and one unit broke on first use. A review says over-pumping can disturb plastic pipework and that a fat obstruction will not move. At 3.4 it is the lowest star line in this set.
Pros
Cons
Best for: A round shower waste, if the unit you receive actually holds pressure on the first blast.
Less suitable: A square toilet pan, or any job where 3.4 from 51 reviews is not enough evidence.
Specifications
Common questions
What heads are in the box?
The listing includes an air pump, a big plunger and a small plunger. Cup diameters are not stated
Does the listing state a pressure?
No bar or psi figure is printed. The rating on the listing is 3.4 from 51 reviews.
Are showers and toilets named?
Yes. The bullet names sinks, toilets, tubs and showers.
The number on each card is the amazon.co.uk star rating multiplied by 20 and rounded. A 4.3 becomes 86. A 3.4 becomes 68. No second cut was applied for review volume, a missing pressure figure or a clash of units. Those points are written in the assessment. The checks below are how the notes were organised. They are not a laboratory weighting. Best value is not the lowest shelf price. There is no measured pressure, and no UKCA, WRAS or BS EN 12056 mark on these listings. One listing prints CE.
Mechanism
25%A stored-air gun has a pump, a valve and a trigger. A force pump is stroked for a light sink, shower or bath blockage and is not a toilet gun. A dual-cup plunger is stroked, with no trigger and no stored cylinder.
Adaptor and the waste
25%English Approved Document H minimum traps are 32 mm for a washbasin, 40 mm for a bath, shower or sink, and 75 mm or 100 mm for a WC outlet. A large WC cup will not seal a shower tray. A small bell can miss a recessed kitchen waste.
Charge and a quotable pressure
20%Keep the first charge low on plastic. Silverline says four pumps on plastic or fragile systems. A line of about 12 times atmospheric pressure is that listing's wording, not a shared test. 8 bar is not 8 psi.
Where the reviews were written
20%Prefer a large United Kingdom sample. The card score is still the amazon.co.uk star line scaled to 100. A listing in which most printed reviews are not from the UK is described in the assessment and is not subtracted again.
Price against the UK sample
10%Best value is not the lowest shelf price. The JJX at about £8.99 has nine United Kingdom reviews in the saved listing, so it is not best value. Shelf prices here run from about £8.99 to about £22.99.
You are choosing a tool for a slow basin, sink, bath, shower or WC, instead of a corrosive cleaner. The ten amazon.co.uk listings captured on 21 October 2026 run from about £8.99 to about £22.99. A stored-air gun, a suction-pressure force pump and a dual-cup plunger are not the same tool. The cup has to seal the waste, the first charge on plastic stays low, and a pressure figure only counts when the units agree. The top pick is the RoPump when the blockage is a light sink, bath or shower.
A drain blaster stores compressed air and lets it go through a rubber adaptor. Buyers use one on a slow basin, sink, bath, shower or WC instead of a corrosive cleaner. Three mechanisms show up on amazon.co.uk. A stored-air gun has a pump, a non-return valve and a trigger. A suction-pressure force pump is stroked by hand for a light blockage in a sink, shower or bath connection, and it is not a charged toilet gun. A dual-cup plunger is stroked. It has no trigger and no stored cylinder.
A large WC cup will not seal a shower tray. A small bell can miss a recessed kitchen waste. English Approved Document H minimum traps are 32 mm for a washbasin, 40 mm for a bath, shower or sink, and 75 mm or 100 mm for a WC outlet.
Silverline says four pumps on plastic or fragile systems. Wonkee Donkee uses about 3 to 8 pumps, fewer on delicate pipework. One UK review says a high first release can force sink joints apart. Block the overflow before you discharge.
Do not blast into a drain that already holds cleaner. GOV.UK says sodium hydroxide burns skin and eyes. NHS Wales notes that liquid drain solvents can boil water in a closed drain and blow push-fittings. If more than one home is affected, call someone and say what you used.
A stored-air gun has a pump, a non-return valve and a trigger. A force pump is stroked for a light sink, shower or bath blockage and is not a toilet gun. A dual-cup plunger is stroked, with no trigger. English Approved Document H minimum traps are 32 mm for a washbasin, 40 mm for a bath, shower or sink, and 75 mm or 100 mm for a WC outlet. A large WC cup will not seal a shower tray, and a small bell can miss a recessed kitchen waste.
Keep the first charge low on plastic. Silverline says four pumps on plastic or fragile systems. A line of 10 to 20 strokes, or about 12 times atmospheric pressure, is that listing's wording, not a shared test. 8 bar is not 8 psi, so a gauge printed with both units is not a figure you can quote. The RoPump listing states 50 psi. Prefer a large United Kingdom sample. The cheapest gun in this set has nine UK reviews in the saved listing, which is why shelf price alone does not decide best value.
Three typical situations, each with a recommendation from this comparison.
You have a light blockage in a sink, bath or shower and you will stroke a force pump. The Rothenberger RoPump 71991 is the top pick at about £21.92, 4.3 from 5,304 reviews, with 50 psi stated. Skip it for a WC. A reviewer's bell, about 95 mm, missed a recessed kitchen waste.
Your pan takes a large cup and you accept splash. The XREXS dual-cup plunger is best value at about £12.34, 4.0 from 3,987. The 15 cm cup is stated for toilets. It is a plunger you stroke, not a trigger gun. The bowl contents can be drawn upward.
You want a trigger gun and a few hundred reviews marked United Kingdom. The HzNzYHD at about £14.99 is 4.2 from 536, and the first 50 in the saved listing are marked United Kingdom. The 12-times pressure line is untested. Some sinks need a larger cup.
The top pick is the Rothenberger RoPump 71991 at about £21.92. It scores 86, the highest here: 4.3 from 5,304 amazon.co.uk reviews, a stated 50 psi, and a 360 g force pump for a light sink, bath or shower blockage. It is not a toilet gun. Best value is the XREXS dual-cup plunger at about £12.34, 4.0 from 3,987, score 80. The JJX at about £8.99 is not best value because the saved listing holds nine United Kingdom reviews. XMPEKO and inShareplus also score 80 and do not take it.
Rothenberger RoPump 71991
Highest score at 86: 4.3 from 5,304 reviews, 50 psi stated, for a light sink, bath or shower. Not a WC.
XREXS drain buster, two cups
About £12.34, 4.0 from 3,987. A stroked dual cup. The gun at about £8.99 has nine UK reviews in the saved listing.
Editorial
Peter F. is the editor for DIY & tools at productscompared.co.uk. Comparisons in this category are checked against amazon.co.uk listings, review evidence and public UK sources.
Guides on what to look for, how to use a product, and common mistakes.
Public UK sources and the amazon.co.uk listings compared on this page. Listings captured 21 October 2026. Updated 22.10.2026.
This page contains affiliate links to amazon.co.uk (tag pcuk26-21). If you buy through them, we may earn a commission at no extra cost to you. Prices, stars and review counts are the amazon.co.uk figures already stored for this set. This is not a laboratory test.
