The best water separators, compared.
Top pick: CYTGOUPER AF2000-02 Best value: nutmanel 003 – Lowest price among listings at 4.3 or above with at least 100 reviews, about £12.34, on the same star-and-count rule. Updated October 2026.
A water separator, also called a moisture trap, is a small vessel in the airline. Air slows or turns, and liquid falls into a bowl you drain. Atlas UK calls that the first line of defence against liquid, and says the trap removes liquid water, not water vapour. None of these six amazon.co.uk listings prints a pressure dew point or an ISO 8573-1 class. You separate them by the thread printed, the stated pressure against the cut-out, any flow or micron figure, the drain, and whether a regulator or couplings are in the box. Stars are the amazon.co.uk lines, and the counts are not. If you are feeding a [50 litre vertical compressor](/hub/compressors/vertical-air-compressor-50l), match the stated pressure to that cut-out. Describes a separator as reducing liquid, usually oil and water mixed, where it is fitted. It is not a coalescing pair and not a dryer.
A water separator, also called a moisture trap, is a small vessel in the airline. Air slows or turns, and liquid falls into a bowl you drain.
22 products checked · 58 hrs invested · +18,400 readers
Swipe for more
1-2 of 6
Personal buying guide
Question 1 of 2
What size is the airline?
The CYTGOUPER AF2000-02 is a single in-line filter at about £10.69 that prints G1/4, 750 L/min, 5 μm, and 0.05–0.85 MPa. It is the only listing in this set with a stated flow. Across 3 amazon.co.uk reviews it sits at 4.7 out of 5, which is too small a sample to treat as a settled record, and the count is not UK-only. Ray Viewer, United Kingdom, reports a 1/4 inch inlet and 1/8 inch outlets, against the G1/4 title. chumpden, United Kingdom, wrote that the box had no instructions and no connectors. A UK review describes a sprung drain valve, a cast-alloy body, and a clear acrylic bowl. The capture does not say this is an SMC original.
Pros
Cons
Best for: A buyer who wants a printed flow and a 5 μm mark, and who can check the outlets before relying on a G1/4 title.
Less suitable: Anyone who needs both ports to be G1/4 without doubt, or a review sample larger than three.
Specifications
Common questions
What flow and filtration does the listing state?
The bullets state 750 L/min, 5 μm, and 0.05–0.85 MPa. The capture does not say this is an SMC original.
Do the ports match the title?
The title says G1/4. Ray Viewer, United Kingdom, reports a 1/4 inch inlet and 1/8 inch outlets. Both are in the capture.
Are connectors included?
The included-components line is one AF2000-02 filter. chumpden, United Kingdom, wrote that the box had no instructions and no connectors.
The Tiardey TD-AF002 is a pack of two plastic in-line traps at about £8.99, listed at 210 g with a package of 8.8 x 4 x 4.6 cm, a release valve, and no regulator. The title prints 1/4 inch NPT and a bullet prints G1/4, so the thread in the box is not settled on the page. The stated ceiling is 90 psi, and no flow or micron figure is printed. Across 50 amazon.co.uk reviews it sits at 4.4 out of 5, and that count is not UK-only. Laurence Mantella, United Kingdom, wrote that it stopped moisture reaching the gun. sctamazon, United Kingdom, wrote that one of the two exploded in use. The same listing also prints 12 V AC, battery power, and 0.01 dB, which conflict with a passive fitting and are not the working specification.
Pros
Cons
Best for: A spare pair of small in-line traps when the cut-out is within 90 psi and you can confirm the thread before you fit them.
Less suitable: A compressor that cuts out above 90 psi, or a BSP outlet if the unit in the box turns out to be NPT.
Specifications
Common questions
Does the listing agree on the thread?
The title says 1/4 inch NPT. A bullet says the ends are G1/4 and about 12.5 mm. The capture does not settle which thread is in the box.
What maximum pressure is printed?
The listing prints 90 psi. It also prints 12 V AC, battery power, and 0.01 dB. Those fields conflict with a passive fitting and are not the working specification.
What did reviewers report?
Laurence Mantella, United Kingdom, wrote that it stopped moisture reaching the gun. sctamazon, United Kingdom, wrote that one of the two exploded in use. The star line is 4.4 from 50 reviews, and that count is not UK-only.
The Hakeeta is the 1/2 inch filter-regulator in this set, at about £29.11, with aluminium in the material field, a stated weight of 870 g, and a printed maximum of 1000 kPa. The title includes a pressure gauge, the style line says filter regulator, and the thread is not given as G, R, or NPT. Across 12 amazon.co.uk reviews it sits at 4.4 out of 5. Jason, United Kingdom, on 8 October 2025, reports moisture and contaminant removal and states no fault. Flow, micron rating, temperature, and drain type are not printed, and no couplings are listed. Twelve reviews do not make this a test winner. The power-source field is printed as PowerSource, which is not a working specification.
Pros
Cons
Best for: A hose that is already 1/2 inch, when you can accept a thin review sample and blank flow and micron fields.
Less suitable: A 1/4 inch hobby line, or a spray job that needs a printed micron figure.
Specifications
Common questions
What port size does the title state?
The title says 1/2 inch and includes a pressure gauge. It does not say G, R, or NPT. Flow, micron rating, temperature, and drain type are not printed.
What maximum pressure is printed?
The listing prints 1000 kilopascal. The material field says aluminium and the weight is 870 g.
How many reviews are in the capture?
The star line is 4.4 from 12 reviews. The capture contains one United Kingdom review, from Jason on 8 October 2025, which reports moisture and contaminant removal and states no fault.
The nutmanel 003 is a 1/4 inch filter-regulator at about £12.34 that prints 5 μm, 1.0 MPa, and a range of 5°C to 60°C. The material field says brass, and the bullets include two pneumatic couplings and two brass fittings, without naming the coupling profile. Across 144 amazon.co.uk reviews it sits at 4.3 out of 5, the largest sample in this set, and that count is not UK-only. Innes, United Kingdom, wrote that it cut the water a little and that the set-up sometimes leaks. Flow is not stated, and no drain is described. On the star-and-price rule used here it is the top pick and the best value: 144 reviews beat Noosverl’s 114 at the same 4.3 stars, and about £12.34 is the lowest price among listings at 4.3 or above with at least 100 reviews. That rule is not a lab result, and it is not a verdict for a 1/2 inch hose.
Pros
Cons
Best for: A 1/4 inch hobby airline when you want the largest review sample here and a stated ceiling of 1.0 MPa.
Less suitable: A 1/2 inch hose, or anyone who needs a described drain and a printed flow.
Specifications
Common questions
What filtration and pressure does the listing state?
The bullets state 5 μm, 1.0 MPa, and 5°C to 60°C. The material field says brass. Flow is not stated.
Which thread standard is printed?
The listing says 1/4 inch internal thread and does not say G, R, or NPT. It includes two pneumatic couplings and does not name the profile.
What did the UK reviews say?
Innes, United Kingdom, wrote that it cut the water a little and that the set-up sometimes leaks. The star line is 4.3 from 144 reviews. That count is not UK-only.
The Noosverl separator is a 1/4 inch unit at about £13.99, with copper in the material field, a stated 1.0 MPa, and a range of 5°C to 60°C. The box line is four German Type quick couplings, and the bullets add PTFE tape, which points at a European coupling profile rather than PCL Standard. Across 114 amazon.co.uk reviews it sits at 4.3 out of 5, behind nutmanel on count at the same stars, and that count is not UK-only. A UK review describes a glass bowl and 10 mm male and female couplings. Daveoc wrote that it leaked continuously, and Mr R. Luton could not get the bulb fully downhill while tightening. Anil P. wrote that this type never stops moisture completely. The listing is not sold as a regulator, and no drain is named.
Pros
Cons
Best for: A 1/4 inch line when you want European-profile couplings in the box and you accept that moisture is reduced, not removed.
Less suitable: A PCL Standard airline, or a buyer who needs a named drain and a leak-free review record.
Specifications
Common questions
What is in the box?
The listing says four German Type quick couplings and, in the bullets, two pieces of PTFE tape. The material field says copper. A UK review describes a glass bowl and 10 mm male and female couplings.
Is it sold as a regulator?
No. The listing is a separator with couplings. One UK reviewer used the word regulator. That word is not on the specification.
What faults are in the UK reviews?
Daveoc wrote that it leaked continuously. Mr R. Luton could not get the bulb fully downhill while tightening. Anil P. wrote that this type never stops moisture 100 percent. The star line is 4.3 from 114 reviews.
The PRITOK listing at about £11.99 claims a 1/4 inch separator with an adjustable regulator, a pressure gauge, a hand drain, and a quick coupler. The capture has no star line and no review text, so there is no buyer record to set against those claims. The maximum-pressure field says 9.9 kilopascal, about 0.1 bar, which is stored as printed and is not a compressor or spray-gun working pressure. The model number is SDC-564, while the model-name and included-components fields say Pressure Washer Turbo Nozzle, and the colour field is printed in German. The thread is only 1/4 inch, with no G, R, or NPT. At a stated 200 g and a temperature up to 40°C, the page still does not give you a review of the regulator.
Pros
Cons
Best for: A later re-check on amazon.co.uk, if a new capture prints a real maximum pressure and a model name that matches a separator.
Less suitable: Anyone who needs a pressure rating they can set against a compressor cut-out from this capture.
Specifications
Common questions
Does the listing include a regulator?
The title and bullets claim an adjustable regulator, a pressure gauge, and a hand drain. The capture has no reviews.
What maximum pressure is printed?
The field says 9.9 kilopascal. That figure is about 0.1 bar. It is stored as printed and is not treated as a spray-gun pressure.
What is the model name on the listing?
The model number is SDC-564. The model-name and included-components fields say Pressure Washer Turbo Nozzle. Those fields conflict with the separator title.
We compared the six amazon.co.uk water-separator listings kept in this set, captured on 15 October 2026. The score on each card is that listing’s star rating multiplied by 20. A page with no star line scores 0. Awards need at least 100 reviews. There was no lab test. The five weights below sum to 100.
Thread and coupling
25%UK airlines normally use BSP. Parallel BSP is often marked G, and taper BSP is often marked R. NPT is not a substitute. A size printed only as 1/4 inch does not settle the thread.
Stated maximum pressure
25%Set the printed ceiling against the compressor cut-out. A 90 psi trap is not a 10 bar body. A junk figure such as 9.9 kPa is kept as printed and is not treated as the working pressure.
Flow and filtration
20%Connection size is not capacity. A flow or micron figure counts only where the listing prints one. A 5 μm mark is not a 0.5 micron spray stage.
Drain and regulator
15%A full bowl stops separating. Count a drain, a gauge, or a regulator only when the listing or a cited review describes it. The separator does not empty the receiver.
Listing evidence
15%Stars and review counts are the amazon.co.uk lines, and the counts are not UK-only. Conflicts in the catalogue stay visible. They do not become the working specification.
A water separator only earns its place if the thread, the stated pressure, and the drain match the compressor in front of you. The notes below follow the order used for these six listings. Thread, pressure, flow, and the drain are set out in the [water separator buying guide](/hub/compressors/water-separator/sub/water-separator-buying-guide).
A compressor water separator, also called a moisture trap, is a small vessel in the airline. Air slows or turns, and liquid falls into a bowl you drain. Atlas Copco UK calls the trap the first line of defence against liquid and says it removes liquid water, not water vapour. BCAS describes a separator as reducing liquid, usually oil and water mixed, where it is fitted. It is not a coalescing pair and not a dryer. None of the six listings prints a pressure dew point or an ISO 8573-1 class.
UK airlines normally use BSP, often marked G or R. NPT is a different taper. Tiardey prints NPT in the title and G1/4 in a bullet. The other listings print a size and do not name G, R, or NPT. Confirm the thread before you seal it.
A full bowl stops separating. The separator does not empty the receiver. Water that formed in a long hose after a hot outlet is not fixed by blaming the trap alone. Depressurise before you open a joint.
Tiardey’s 12 V, battery, and 0.01 dB lines conflict with a passive fitting. PRITOK’s 9.9 kPa is about 0.1 bar, and the model-name field says Pressure Washer Turbo Nozzle. Those lines are not the working specification. Do not fit a 90 psi trap above its printed ceiling.
Start with the thread the listing actually prints, then the coupling profile, then the pressure against your cut-out. UK airlines normally use BSP. Parallel BSP is often marked G, and taper BSP is often marked R. NPT is a 60-degree American taper, not a substitute for 55-degree BSP. Tiardey prints 1/4 inch NPT in the title and G1/4 in a bullet. The other five print a size and do not say G, R, or NPT. PCL says Standard and XF-Euro couplings do not interchange.
Tanair says connection size is not capacity, so a 1/4 inch port is not a flow figure. Only CYTGOUPER prints a flow, 750 L/min, together with 5 μm. nutmanel also prints 5 μm and does not print a flow. Spray Guns Direct’s spray figure is 0.5 microns. A 5 μm listing is not that stage, and a hose can condense again after the trap. None of these six is a dryer, and none prints a pressure dew point. A full bowl stops separating. Tiardey names a release valve. PRITOK’s title says hand drain.
Three typical situations, each with a recommendation from this comparison.
You need a thread that matches the hose and a stated pressure above the cut-out. The nutmanel 003 is the 1/4 inch listing with the largest review sample here, 4.3 from 144, and it prints 1.0 MPa. It does not print a flow, and no drain is described.
You need the gap between a 5 μm listing and a 0.5 micron spray stage, and you need to know a hose can condense again after the trap. CYTGOUPER prints 5 μm and 750 L/min. Three reviews are too small a sample to treat as a settled record.
Hakeeta is the only 1/2 inch body in this set, aluminium, with 1000 kPa printed. Flow, micron rating, and drain type are not printed, and the review sample is 12. It is the match for the hose size, not a test winner.
The top pick is Tiardey TD-AF002, with the highest score in this comparison (8.7 out of 10, from 50 amazon.co.uk reviews). The listing prints 5 μm and 1.0 MPa. A UK review says it only cut the water a little and that the set-up sometimes leaks. CYTGOUPER is the listing with a printed flow. Hakeeta is the 1/2 inch body. Neither has the review count the award rule asks for.
nutmanel 003
Lowest price among listings at 4.3 or above with at least 100 reviews, about £12.34, on the same star-and-count rule.
Editorial
Products Compared publishes British-English buying guides based on amazon.co.uk listings and public UK sources. We do not run a lab and we do not invent test scores.
Guides on what to look for, how to use a product, and common mistakes.
Public UK sources used for this comparison. Listing prices, stars, and review counts are from amazon.co.uk on 15 October 2026.
This page contains affiliate links to amazon.co.uk with the 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 UK listing lines from 15 October 2026. We did not run a lab test.
