The best Smoke alarm magnets, compared.
Top pick: ECENCE 70 mm magnetic mount, 10 pieces – Highest score, 95, for a stated 70 mm plate, a 500 g claim, and 4.6 from 2,047 reviews, at about £11.99. Best value: ECENCE 50 mm magnetic mount, 10 pieces – About £10.99, about £1.10 a plate, with a stated 50 mm diameter and a score of 93. Updated October 2026.
A smoke alarm magnet is a pair of self-adhesive metal plates with a magnet between them, so you can hang a battery alarm without screws and slide it off later. None is a smoke alarm, and none meets BS EN 14604, which applies to the alarm. Buy a plate only after you have measured the flat back of an alarm you already own and checked that the ceiling is smooth, sound, and dust-free. Falls are usually the adhesive leaving the paint. The [smoke alarm magnet buying guide](/hub/fire-protection/smoke-alarm-magnet/sub/smoke-alarm-magnet-buying-guide) sets out whether a plate is the right fixing, including when to walk away. You stick one side to a smooth ceiling and the other to the flat back of a battery alarm, then slide the alarm off when you need the battery.
A smoke alarm magnet is a pair of self-adhesive metal plates with a magnet between them, so you can hang a battery alarm without screws and slide it off later.
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Personal buying guide
Question 1 of 2
What size is the flat back of the alarm?
The ECENCE 70 mm ten-pack is ten self-adhesive plates at about £11.99 on amazon.co.uk, with 4.6 from 2,047 reviews, and it is the only kept listing whose title states a 70 mm disc. The bullets claim a 500 g maximum load, tell you to press the pad for 10 seconds, and say to push the alarm sideways off the plate. There is no smoke alarm in the box, and those bullets do not give a cure time in hours. Trade sellers such as Safelincs use a 70 mm plate for bases around 70 mm, so this pack is the size match when you are hanging several ordinary battery alarms on a smooth ceiling. Only six of the first 50 reviews in the file are from the United Kingdom, so the 2,047 figure is not a UK-only verdict. The 500 g line is a claim: the failure buyers describe on these mounts is the adhesive leaving the paint, not a weak magnet. At about £1.20 a plate it is the top pick for large flat backs, and a poor buy on Artex, fresh filler, or if you still need the alarm itself.
Pros
Cons
Best for: You have several battery alarms with a flat back around 70 mm and a smooth, sound ceiling.
Less suitable: The ceiling is textured or freshly filled, the alarm is mains-powered, or you still need to buy the alarm itself.
Specifications
Common questions
Does this pack include a smoke alarm?
No. The listing highlight describes magnetic adhesive pads for smoke alarms. There is no included-components line naming an alarm.
What size and load does the listing state?
The title says 70 mm. The bullets say a maximum load of 500 g. They also say to press the pad for 10 seconds.
How does the listing say you take the alarm down?
Push the alarm sideways off the mounting plate. The listing does not give a cure time in hours.
The ECENCE 50 mm ten-pack costs about £10.99 and carries 4.6 from 1,842 amazon.co.uk reviews, with the same 500 g bullet and the same ten-second press as the 70 mm set. Ten plates come out at about £1.10 each, the lowest price per plate in this comparison, which is why it is the best value pack when the alarms are compact enough for a 50 mm disc. The listing photo uses the same image URL as the three-piece 50 mm page, so the pack size is the title, not the picture. The page does not include an alarm and does not print a wait in hours. A review on the three-piece file called 50 mm unsuitable for larger and interlinked alarms, and that size limit applies to this disc as well. Both 50 mm listings also print the same Best Sellers Rank line, so you should not add the two ranks together. Choose it for several small battery alarms on a flat, sound ceiling, and leave it if the flat back is nearer 70 mm or the paint is textured.
Pros
Cons
Best for: You are fitting several compact battery alarms and want the lowest price per plate in this set.
Less suitable: The flat back is about 70 mm or more, or you are choosing the pack from the photo rather than the title.
Specifications
Common questions
Does this pack include a smoke alarm?
No. The listing is a 10-piece magnetic mount. The included-components line is missing, and the highlight describes adhesive pads.
What size and load does the listing state?
The title says 50 mm. The bullets say a maximum load of 500 g and a 10-second press when fitting.
Is the photo unique to this 10-piece pack?
The saved listing uses the same image URL as the ECENCE 3-piece 50 mm listing, B07G1BF811. Pack size comes from the title, not from that photo.
The ECENCE three-piece 50 mm set is about £5.99, rated 4.5 from 1,245 amazon.co.uk reviews, and the contents line names three self-adhesive magnetic holders rather than a detector. The title says 50 mm, the bullets claim 500 g, the material line says metal, and the item weight is 68 g. At about £2 a plate it costs more per disc than either ten-pack, which is what you pay to avoid seven spare plates. Reviews on this file include long holds and alarms that fell after days, and one called the 50 mm size unsuitable for larger and interlinked units. The product image is shared with the ten-piece 50 mm listing, so do not count plates from the photo. A catalogue field that calls the alarm audible is not a sounder in the box. It suits one hallway plus a spare on a small flat back, and it is the weaker buy if you need ten plates or a 70 mm contact patch.
Pros
Cons
Best for: You need three 50 mm plates for small flat-backed battery alarms and do not want a ten-pack.
Less suitable: You have full-size or interlinked alarms, or you want the lower price per plate of a ten-pack.
Specifications
Common questions
Does this pack include a smoke alarm?
No. Included components are 3 self-adhesive magnetic holders. A catalogue row says the alarm is audible, which is not a sounder in that contents line.
What size and load does the listing state?
The title says 50 mm. The bullets say a maximum load of 500 g. Material is listed as metal and the item weight as 68 g.
How does the listing say you take the alarm down?
Push it sideways off the plate. The bullets say to press for 10 seconds when fitting. They do not state a wait in hours.
The IME three-piece set is about £5.99, the same shelf price as the ECENCE three-piece, but amazon.co.uk shows 3.8 from 56 reviews. The dimensions are 5 × 5 × 1 cm and the item weight is 90 g, with no diameter and no load in grams, so you cannot match a printed disc size to the flat back of your alarm. The bullets name 3M tape, while a UK review in the file says the sticky pad is not 3M branded. Several reviews say the alarm fell within a week, and others say the glue failed while the magnets still felt strong. The listing states that no alarm is included. At about £2 a plate, with a thin review file and no stated diameter, it is the pack to leave unless you have already checked a square pad against your alarm and you accept those fall reports. A slightly textured ceiling is the surface those reviews say the pad does not hold.
Pros
Cons
Best for: You have measured a square pad of about 5 cm against a small alarm and accept a thin review file.
Less suitable: You need a stated diameter, a stated load, or a pack with a large amazon.co.uk review file.
Specifications
Common questions
Does this pack include a smoke alarm?
No. The listing field for alarm is no. The product is a 3-piece magnetic sticky pad.
What size and load does the listing state?
Dimensions are 5 × 5 × 1 cm and the item weight is 90 g. No diameter and no load in grams are stated.
Does the listing say the tape is 3M?
The bullets say 3M glue tape and three magnets. A UK review in the saved listing says the sticky pad is not 3M branded.
Four amazon.co.uk plates were scored out of 100 from the shelf prices, stars, and review counts stored with this comparison. The parts are stars, the size of the review file, how clearly the listing states diameter, load, and that no alarm is included, and price per plate. A thin UK share in the early reviews, and named falls, are deductions on top of those parts. This is not a lab test, a British Standard, or a fire-service approval. The four weights below sum to 100.
Stars
40%Maximum 40. The amazon.co.uk star rating divided by 5, then multiplied by 40.
Review file
20%Maximum 20. A file of 2,000 or more ratings scores 20, 1,500 or more scores 18, 1,000 or more scores 16, and under 100 scores 6.
Listing clarity
20%Maximum 20. Eight points for a diameter in the title, six for a numeric load, four when the page makes clear there is no alarm, and two when the photo is not shared with another kept listing.
Price per plate
20%Maximum 20. Among packs that state a diameter, the lowest price per plate scores 20 and the others are scaled against it. A pack with no diameter scores a flat 8.
These four listings are mounts, not detectors. Confirm the box contains plates, then measure the flat back of an alarm you already own. Match a 70 mm disc to a larger base and a 50 mm disc to a compact alarm. Skip Artex, woodchip, gloss, dust, and fresh filler. Read the alarm manual before you leave out its screws. A 500 g bullet is a claim, not proof the alarm will stay up. Pack size should follow how many alarms you are fitting. The ten-packs are the lower price per plate.
A smoke alarm magnet is a pair of self-adhesive metal plates with a magnet between them. You stick one side to a smooth ceiling and the other to the flat back of a battery alarm, then slide the alarm off when you need the battery. The four products kept here are plates only: ECENCE 50 mm in a three-piece and a ten-piece pack, ECENCE 70 mm in a ten-piece pack, and an IME three-piece set. None is a smoke alarm. BS EN 14604 applies to the alarm, not to a third-party plate.
The ECENCE bullets claim a 500 g maximum load. That is not proof the alarm will stay up. Reviews describe the adhesive leaving the paint, including on light alarms. Do not copy a 550 g figure from a different ECENCE page onto the 70 mm ten-pack. The IME listing states no load in grams.
Trade pages pair 70 mm plates with bases around 70 mm or more, and 50 mm plates with smaller alarms. A review on the 50 mm three-piece called that size unsuitable for larger and interlinked alarms. The same limit applies to the 50 mm ten-pack. Ribs on the back shrink the glue contact.
Skip textured, papered, glossy, dusty, or fresh filler. ECENCE bullets say press for 10 seconds. They do not print a wait in hours. Safelincs says wait one hour, and other UK texts say 24 hours. Push the alarm sideways off the plate. Do not pull it straight down.
Confirm the listing is the plate, not an alarm. The IME page states that no alarm is included. The ECENCE three-piece contents line names three self-adhesive magnetic holders. Then measure the flat back. The ECENCE 70 mm title is the diameter trade kits use for a larger base. The 50 mm title is the small-alarm size. A review on the three-piece file called 50 mm unsuitable for larger and interlinked alarms, and that limit applies to the 50 mm ten-pack as well.
Skip textured, papered, glossy, dusty, or fresh filler. Safelincs wants a flat, clean surface, with matt emulsion in mind. Bellman excludes vinyl, silicone, and Teflon-style coatings. Read the alarm manual before you skip its screws. A light battery alarm is the plausible case. A mains head is not. A 500 g line on the ECENCE bullets is a claim, not proof the alarm will stay up. Do not copy a 550 g figure from a different ECENCE page onto the 70 mm ten-pack.
Three typical situations, each with a recommendation from this comparison.
You already own battery alarms with a flat back around 70 mm, and the ceiling is smooth and sound. The ECENCE 70 mm ten-pack is about £11.99, score 95, with 4.6 from 2,047 reviews. There is no alarm in the box. Only six of the first 50 reviews are from the United Kingdom.
The alarms are small enough for a 50 mm disc and you want ten plates. The ECENCE 50 mm ten-pack is about £10.99, about £1.10 a plate, score 93, with 4.6 from 1,842 reviews. The listing photo is shared with the three-piece page, so the pack size is the title.
You need three 50 mm plates and you do not want seven spare discs. The ECENCE three-piece is about £5.99, about £2 a plate, score 78, with 4.5 from 1,245 reviews. Reviews on that file include falls after days, including on larger alarms.
The top pick is the ECENCE 70 mm ten-pack, score 95, at about £11.99. The title states 70 mm, the bullets claim 500 g, and amazon.co.uk shows 4.6 from 2,047 reviews. That review file is not UK-only. The best value is the ECENCE 50 mm ten-pack, score 93, at about £10.99, about £1.10 a plate, for compact battery alarms. The three-piece 50 mm pack is the short run at about £2 a plate, and the IME three-piece is the same shelf price with 3.8 from 56 reviews and no stated diameter. None of these scores is a laboratory hold test.
ECENCE 70 mm magnetic mount, 10 pieces
Highest score, 95, for a stated 70 mm plate, a 500 g claim, and 4.6 from 2,047 reviews, at about £11.99.
ECENCE 50 mm magnetic mount, 10 pieces
About £10.99, about £1.10 a plate, with a stated 50 mm diameter and a score of 93.
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 from the research digest, retrieved 20 October 2026. Listing prices, stars, and review counts are the amazon.co.uk figures stored with this comparison.
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 stored UK listing lines. We did not run a laboratory hold test.
