Best medium strength threadlocker
Updated: October 2026
You need one bottle for a metal bolt you will undo later. The best medium strength threadlocker in this amazon.co.uk set is a conditional choice: a medium-only blue bottle whose listing and UK reviews agree that the fastener can still come apart. A higher star line or the number 243 on the title can each be a different buy. The full table stays on the [threadlocker medium strength comparison](/hub/diy-supplies/threadlocker-medium-strength). Peter F. read these listings on 15 October 2026. There is no laboratory winner. A qualifying purchase through our links can earn us a commission at no extra cost to you.
You need one bottle for a metal bolt you will undo later.
You need one bottle for a metal bolt you will undo later. The best medium strength threadlocker in this amazon.co.uk set is a conditional choice: a medium-only blue bottle whose listing and UK reviews agree that the fastener can still come apart. A higher star line or the number 243 on the title can each be a different buy. The full table stays on the threadlocker medium strength comparison. Peter F. read these listings on 15 October 2026. There is no laboratory winner. A qualifying purchase through our links can earn us a commission at no extra cost to you.
Our top picks
| Badge | Product | Removal | Cure | Limit | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Vigorder Vigorder blue 50 ml | Not printed | 20 min, then 24 hours | 22 reviews | 9.6 | about £7.99 | View offer |
| Alternative |  Loctite Loctite 243 blue 5 ml | Grade 243 on the title | Full cure 24 hours | Aerosol and plastic cells | 9.4 | about £12.59 | View offer |
 Bäder Bäder B243Eco blue 10 ml | UK reviews: still undone | No clock printed | Not grade 243 | 9.4 | about £5.39 | View offer |
On this page
What this page is choosing
The job is a serviceable metal thread. Sorting by stars puts Vigorder first: 4.8 from 22 reviews, at £7.99, with a metal-only bullet and a 20-minute then 24-hour clock. That file holds five UK reviews and does not print hand-tool removal.
Sorting by millilitre price is just as misleading. £12.59 for 5 ml of Loctite 243 is about £2.52 per ml, and a 50 ml unbranded blue can look like £0.16 to £0.18 per ml. You use drops, so the cheap millilitre is not more jobs. The earlier checks are on the medium strength threadlocker buying guide.
The conditional top pick
For a metal bolt you still expect to undo, the top pick in this set is the Bäder B243Eco, a medium-strength blue 10 ml bottle at £5.39. amazon.co.uk shows 4.7 from 229 reviews. The bullet states −55°C to +180°C, with metal as the surface. UK reviews say screws stayed tight and could still be undone. That is the removal story Vigorder does not print.
There is no cure-time cell. A Green Line bullet says non-hazardous, and the file has no safety data sheet. Do not treat B243Eco as Loctite 243. The name is similar. The grade number is not on this title. It is the best value against £12.59 for 5 ml of titled 243, as shelf arithmetic only. Skip it if you need a printed fixture time or the Henkel grade number.
When you want the grade number
Pay for a bottle that prints Loctite 243 when the grade number is the point, then read the cells that fight the title. The 5 ml row is £12.59, with 4.7 from 2,990 reviews. The bullets say all metals and minor contamination, and full cure is 24 hours. UK texts say a few drops work, and that the bottle is small for the money. The container cell says aerosol can, and the material cell says Plastic.
The 50 ml row at £12.00 still titles Loctite 243. The manufacturer cell says DGI, not Henkel, and there is no cure time. A lower price per millilitre does not repair that. Loctite Normal at £6.60 does not print medium or 243, and its colour cell says Transparent. If the pack also contains red, that choice is on blue vs red threadlocker.
Who should skip the pick
Skip every row on this page if the thread is plastic. Permatex says its medium blue is not for plastics. Vigorder’s bullet says metal threads only. Skip the pick if the joint must never come apart. A red bottle in a two-colour pack is the hazard if you grab it for a bolt you service.
Skip brakes, steering and suspension unless the manual names the grade. A UK review is one job, not a torque. Those stories are on the threadlocker for bike bolts page. No row here is treated as food-safe. If you only needed a few drops, the £5.39 Bäder bottle is the coherent medium-only buy. If you needed the number 243 and you can live with the conflicting cells, the 5 ml row is the other buy.
Common questions
Which bottle is the top pick if you will undo the bolt?
The Bäder B243Eco, medium-strength blue, 10 ml, at £5.39. amazon.co.uk shows 4.7 from 229 reviews, the bullet states −55°C to +180°C, and UK reviews say the fastener could still be undone. It does not print a cure time, and it is not Loctite 243. Use it on a metal thread you will service. Leave it if the manual demands another grade.
Is the 50 ml Loctite 243 row the better buy because it is cheaper per millilitre?
No. £12.00 for a titled 50 ml is less per millilitre than £12.59 for 5 ml, and that is only shelf arithmetic. The manufacturer cell says DGI, the pack-quantity cell says 10 against one piece, and there is no cure time. UK reviews include an India-stock complaint and an unlawful claim. Those reviews are not an enforcement finding.
Is the highest star score the top pick?
No. Vigorder’s 4.8 from 22 reviews is the highest star line, at £7.99, with a metal-only bullet and a 20-minute then 24-hour clock. The stored file has five UK reviews and does not say you can undo the bolt with hand tools. The comparison score on the main page sits at the top of this set for that reason. A serviceable bolt still needs a removal story, which is why the conditional pick is the Bäder bottle.
What is the best value if you only need a few drops?
The same 10 ml Bäder bottle at £5.39, set against £12.59 for 5 ml of titled 243. You use drops, so the small pack is enough for a handful of bolts. The best-value case fails if you need a printed cure time or the grade number 243. A £3.99 Flintronic title is cheaper and does not win that case: the colour cell can fight the title, and two ASINs share one review file.
Does a UK review of brake calipers make a bottle the top pick?
No. kintsukuroi has a UK review that used the liquid on caliper bolts, and Bäder’s file mentions BMW calipers. A review is one person’s job. It does not set the torque, and it does not override the vehicle manual. Brakes, steering and suspension stay with the manual, or with a professional if you cannot follow that manual.
Related pages
Sources
Henkel, the Health and Safety Executive, ISO 10964 and the Consumer Rights Act 2015, plus the amazon.co.uk listings read on 15 October 2026. Prices move. Nothing was torque-tested in a lab.
- Henkel UK, LOCTITE 243 (retrieved 15 October 2026)
- Henkel UK, choosing a threadlocker (retrieved 15 October 2026)
- Henkel GB SDS 817149, 11 June 2026 (retrieved 15 October 2026)
- HSE, GB CLP (retrieved 15 October 2026)
- HSE, COSHH (retrieved 15 October 2026)
- ISO 10964:1993 (retrieved 15 October 2026)
- Consumer Rights Act 2015 (retrieved 15 October 2026)
- Permatex medium strength threadlocker blue (retrieved 15 October 2026)
- amazon.co.uk listings, example Bäder B0CFR456YL (retrieved 15 October 2026)