41 Designs shop reference · Henkel LOCTITE data · compiled November 2026

Blue and red threadlockers, side by side

Eleven grades compared on Henkel's own data sheet numbers. Torque is in lb·in on an M10 steel nut and bolt after a 24-hour cure at 72°F unless a cell says otherwise.

Reading the numbers

Breakaway
Torque at first movement on a nut that was run on but not tightened. It is the adhesive alone, with no clamp load.
Prevail
Torque still needed after half a turn. A low number means it lets go once cracked. A high number means it fights all the way off, which is why red chews up threads if you skip the heat.
Breakloose
Same test with the nut tightened to 5 N·m (44 lb·in) first. Closer to a real joint, and usually higher.
Fixture time
When it has set enough to handle. Finish torquing before this. Full strength takes 24 hours.
  • The numbers scale with thread size. 243 breaks at 80 lb·in on M6, 200 on M10 and 440 on M16. Divide lb·in by 12 for ft·lb.
  • On a torqued fastener the threadlocker adds to the joint. These figures are not the removal torque you will see on a wrench.
  • Plating, stainless and cold slow the cure and cut strength on 242, 262, 271, 272 and 277. Henkel's activators are SF 7649 and SF 7471. Henkel's product pages also recommend an activator below 41°F (5°C).
  • Not for plastics. Henkel warns of stress cracking on thermoplastics. Not for pure-oxygen systems either.
  • Store at 46 to 70°F. Henkel says storage below 46°F or above 82°F can change how it performs.
  • You will see other numbers quoted. Henkel's sales sheets list 243 at 230 / 40 lb·in and the 2012 chart lists a 5-minute fixture for 242 and 263. This page uses the current data sheet first.

Which one to grab

Blue comes apart with hand tools. Red is meant to stay and usually needs heat. Inside each color, the number tells you the thread size, the heat it can take, and whether it needs clean, primed threads.

Blue Medium strength, removable

242
Use it for

Clean plain-steel hardware you will service, and jobs or drawings that call out 242 or MIL-S-46163A by name.

Why this one

The original blue. It works on clean steel, but grip falls to 20–60 lb·in on zinc plating and it tops out at 300°F. Keep it for jobs that name it.

243Stock this one
Use it for

The everyday serviceable fastener from 1/4" to 3/4": brackets, skid plates, accessory mounts, anything you expect to take apart again.

Why this one

Cures on plated and stainless hardware and through light oil with no primer, holds to 360°F, and still comes off with hand tools.

248
Use it for

The same jobs as 243 when you are working overhead or under a vehicle and a liquid would run off the threads.

Why this one

The stick stays where you put it. Same 200 lb·in breakaway as 243, no primer, 5-minute fixture. The limit is 300°F.

2422
Use it for

Serviceable 1/2" to 3/4" fasteners that sit in real heat, up to 650°F.

Why this one

The only removable grade rated past 360°F. Prevail is 12 lb·in, so it resists vibration but lets go as soon as it cracks.

Red High strength, permanent

262
Use it for

Permanent fasteners up to 3/4" where you want a thicker liquid that stays on the threads instead of running.

Why this one

It cracks at about the same torque as blue 243, then prevail climbs to 280 lb·in. Needs clean threads, and primer on plated or stainless.

263Stock this one
Use it for

Studs, and nuts or bolts from 1/4" to 3/4" that you do not plan to take apart.

Why this one

Primerless and oil tolerant like 243, good to 360°F, and it holds 290 lb·in the whole way off instead of letting go after the first crack.

268
Use it for

Red in stick form for overhead and hard-to-reach work.

Why this one

Stays put and needs no primer. Breakaway with no preload is low at 90 lb·in, but a tightened fastener takes 355 lb·in to break loose.

271
Use it for

Studs and bolts up to 1" on clean steel, and jobs that call out 271 or the mil-spec.

Why this one

Thin enough to wet fine threads. Strong on plain steel, but breakaway drops to 40–125 lb·in on zinc or cad plating unless you prime it.

272
Use it for

Permanent fasteners that run hot, up to 450°F, in sizes up to 1-1/2".

Why this one

The highest-temperature liquid red. Thick enough to fill coarse threads. Fixture takes 40 to 60 minutes.

277
Use it for

Large studs and bolts, 1" and up.

Why this one

Thick enough to fill the gaps in big threads, and the 45 to 60 minute fixture gives you time to torque a full bolt pattern before it sets.

2620
Use it for

High-strength locking in extreme heat, up to 650°F, on 1/2" to 3/4" fasteners.

Why this one

Rated to 650°F. Unlike the other reds, Henkel says hand tools normally remove it, and prevail is under 10 lb·in.

Torque at a glance

Red is not much harder to crack than blue. 262 breaks at 190 lb·in and 243 at 200. The difference is what happens after it moves: 243 drops to 80, while 262 climbs to 280 and 263 holds 290 the whole way off.

Breakaway, first movementPrevail, after half a turnlb·in on M10 steel
242
110†
43†
243
200
80
248
200
43†
2422
102
12
262
190
280
263
290
290
268
90
34†
271
250†
275†
272
200
220
277
280
280
2620
161
9.7

† Typical value from Henkel's selector chart, because the data sheet gives only a range or no figure. 2422 and 2620 were tested on 3/8-16 bolts after 72 hours. 268 looks weak here because this test has no preload. Tightened to 44 lb·in first, it takes 355 lb·in to break loose.

Maximum service temperature

This is the continuous limit Henkel rates each grade for. Strength falls off as you approach it, and the hot-strength curves on each data sheet show by how much.

300°F150°C
242248262268271277
360°F180°C
243263
450°F232°C
272
482°F250°C
The heat Henkel says to apply to the nut or bolt to break a cured red. Turn it while it is still hot.
650°F343°C
24222620

Every grade here is rated down to −65°F. Exhaust manifold and turbo hardware can run well past 450°F, so check the real temperature of the fastener before trusting 272 there.

Full specifications

Scroll sideways on a narrow screen. † marks a figure from Henkel's 2012 selector chart where the current data sheet is silent.

Blue

Spec 242 243 248 2422
Strength and form
Strength class Medium Medium Medium Medium
Form and viscosity Liquid
900–1,400 cP		 Liquid
1,300–3,000 cP		 Wax stick
Melts above 149°F (65°C)		 Paste
35,000–80,000 cP
Thixotropic Yes Yes n/a Yes
Specific gravity 1.1 1.08 1.03 1.18
Fastener size 1/4" to 3/4" 1/4" to 3/4" 1/4" to 3/4" 1/2" to 3/4"†
Torque on M10 steel, 24 h cure
Breakaway 110 lb·in
12.4 N·m
Typical†. TDS range 71–168		 200 lb·in
22 N·m		 200 lb·in
23 N·m		 102 lb·in
11.6 N·m
3/8-16, 72 h cure
Prevail 43 lb·in
4.9 N·m
Typical†. TDS range 25–60 on 3/8-16		 80 lb·in
9 N·m		 43 lb·in
4.9 N·m
From selector chart†. Not in TDS		 12 lb·in
1.4 N·m
3/8-16, 72 h cure
Breakloose Not published 200 lb·in
22 N·m
270 (30 N·m) on zinc phosphate after 1 week
120 (14 N·m) on stainless		 225 lb·in
25 N·m		 137 lb·in
15.5 N·m
3/8-16, 72 h cure
Other sizes and finishes lb·in 3/8-16 steel: 70–150 breakaway
3/8-16 zinc plated: 20–60
3/8-16 cad plated: 10–60		 M6: 80 breakaway, 9 prevail
M16: 440 breakaway, 180 prevail
3/8-16: 110 breakaway, 70 prevail		 3/8-16 steel: 120 breakaway
3/8-16 stainless: 110 breakaway, 160 breakloose		 24 h breakloose: 70–251
Oily phosphate bolts, as received: 110 breakloose
Temperature and cure
Service temperature 300°F max
−65 to 300°F
−54 to 149°C		 360°F max
−65 to 360°F
−55 to 180°C
Cold tested to −100°F		 300°F max
−65 to 300°F
−55 to 150°C		 650°F max
−65 to 650°F
−54 to 343°C
Fixture time on steel 5–10 min 10 min 5 min 30 min†
Full cure 24 h 24 h 24 h 24 h†
TDS torque is at 72 h
Surface prep and removal
Primer Activator on plated, stainless, aluminum None needed None needed Activator on plated, stainless, aluminum
Oil tolerance Not rated. Degrease first Yes, light oil films Yes
96% strength on solvent-based oil, 61% on emulsion oil		 Tested on oily as-received bolts
Removal Hand tools
Rarely, heat to 482°F (250°C)		 Hand tools
Rarely, heat to 482°F (250°C)		 Hand tools
Rarely, heat to 482°F (250°C)		 Hand tools
Rarely, heat to 482°F (250°C)
Durability
Strength kept after 1,000 h in fluid Motor oil100%Gasoline95%Brake fluid100%Coolant70% Motor oil115%Gasoline95%Brake fluid110%Coolant125% Motor oil90%Gasoline85%Brake fluid100%Coolant95% Motor oil140%Gasoline75%Brake fluid105%Coolant140%
Shear strength pins and collars Not published >1,100 psi
7.6 N/mm²		 Not published Not published
Paperwork
Tested to MIL-S-46163A, ASTM D5363, NSF/ANSI 61†, NSF P1† NSF/ANSI 61† None listed None listed
Data sheet date Feb 2022 Apr 2025 Jan 2014 Jan 2011

Red

Spec 262 263 268 271 272 277 2620
Strength and form
Strength class Medium to high High High High High High Medium to high
Form and viscosity Liquid
1,200–1,400 cP		 Liquid
500 cP		 Wax stick
Melts above 149°F (65°C)		 Liquid
400–600 cP		 Thick liquid
4,000–15,000 cP		 Thick liquid
6,000–8,000 cP		 Paste
20,000–70,000 cP
Thixotropic Yes No n/a No Yes Yes Yes
Specific gravity 1.1 1.1 1.03 1.1 1.11 1.12 1.16
Fastener size Up to 3/4"†
TDS: bolts and studs to M25 (1")		 1/4" to 3/4"
Some Henkel guides say up to 1"		 Up to 3/4"†
Later guides say up to 1"		 Up to 1" (M25) Up to 1-1/2" (M36)
TDS: M25 and larger		 1" (M25) and larger
Guides list up to 1-1/2"		 1/2" to 3/4"†
Torque on M10 steel, 24 h cure
Breakaway 190 lb·in
22 N·m		 290 lb·in
33 N·m		 90 lb·in
10 N·m		 250 lb·in
28 N·m
Typical†. TDS range 150–350		 200 lb·in
23 N·m		 280 lb·in
32 N·m		 161 lb·in
18.2 N·m
3/8-16, 72 h cure
Prevail 280 lb·in
32 N·m		 290 lb·in
33 N·m		 34 lb·in
3.8 N·m
From selector chart†. Not in TDS		 275 lb·in
31 N·m
Typical†. TDS range 200–350		 220 lb·in
25 N·m		 280 lb·in
32 N·m		 9.7 lb·in
1.1 N·m
3/8-16, 72 h cure
Breakloose 340 lb·in
38 N·m
Max prevail 350 (40 N·m)		 345 lb·in
39 N·m
400 (46 N·m) on zinc phosphate after 1 week
265 (30 N·m) on stainless		 355 lb·in
40 N·m		 Not published Not published 340 lb·in
38 N·m
Max prevail 350 (40 N·m)		 247 lb·in
27.9 N·m
3/8-16, 72 h cure
Other sizes and finishes lb·in Not published M6: 45 breakaway, 26 prevail
M16: 800 breakaway, 1,100 prevail
3/8-16: 275 breakaway, 290 prevail		 3/8-16 steel: 90 breakaway, ≥150 breakloose
3/8-16 stainless: 140 breakaway, 205 breakloose		 3/8-16 steel: 150–300 breakaway, 200–355 prevail
3/8-16 zinc or cad plated: 40–125 breakaway		 3/8-16 steel: ≥159 breakaway and prevail Not published 24 h breakloose: 101–301
Oily phosphate bolts, as received: 164 breakloose
Temperature and cure
Service temperature 300°F max
−65 to 300°F
−54 to 149°C		 360°F max
−65 to 360°F
−55 to 180°C
Cold tested to −100°F		 300°F max
−65 to 300°F
−55 to 150°C		 300°F max
−65 to 300°F
−54 to 149°C		 450°F max
−65 to 450°F
−54 to 232°C		 300°F max
−65 to 300°F
−55 to 150°C
Cold tested to −100°F		 650°F max
−65 to 650°F
−54 to 343°C
Fixture time on steel 10 min† 10 min 5 min 10 min† 40–60 min 45–60 min 30 min†
Full cure 24 h 24 h 24 h 24 h 24 h 24 h 24 h†
TDS torque is at 72 h
Surface prep and removal
Primer Activator on plated, stainless, aluminum None needed None needed Activator on plated, stainless, aluminum Activator on plated, stainless, aluminum Activator on plated, stainless, aluminum Activator on plated, stainless, aluminum
Oil tolerance Not rated. Degrease first Yes, light oil films Yes
95% strength on solvent-based oil, 58–66% on other oils		 Not rated. Degrease first Not rated. Degrease first Not rated. Degrease first Tested on oily as-received bolts
Removal Heat to 482°F (250°C), turn while hot Heat to 482°F (250°C), turn while hot Heat to 482°F (250°C) when hand tools will not break it Heat to 482°F (250°C), turn while hot Heat to 482°F (250°C), turn while hot Heat to 482°F (250°C), turn while hot Hand tools
Heat to 482°F (250°C) over 1" or with long engagement
Durability
Strength kept after 1,000 h in fluid Motor oil75%Gasoline100%Brake fluid100%Coolant85%Gasoline figure is leaded petrol Motor oil75%Gasoline95%Brake fluid105%Coolant85% Motor oil65%Gasoline100%Brake fluid90%Coolant75% Motor oil75%Gasoline95%Brake fluid100%Coolant85% Motor oil62%Gasoline62%Brake fluidn/aCoolant58%Different test: 720 h at 189°F. Coolant figure is water Motor oil100%Gasoline100%Brake fluid100%Coolant90% Motor oil134%Gasoline100%Brake fluid100%Coolant118%
Shear strength pins and collars ≥1,450 psi
10 N/mm²		 ≥1,305 psi
9.0 N/mm²		 Not published Not published ≥2,102 psi
14.5 N/mm²
≥2,900 psi when aged and tested at 392°F		 ≥1,300 psi
9 N/mm²		 Not published
Paperwork
Tested to MIL-S-46163A, ASTM D5363, NSF P1† NSF/ANSI 61 None listed MIL-S-46163A, ASTM D5363, UL classified None listed MIL-S-46163A, ASTM D5363 None listed
Data sheet date Feb 2022 May 2025 2013 spec, 2017 print Mar 2012 Dec 2013 May 2022 Nov 2019

Purple and green, for context

The two other colors you will see on the shelf.

GradeUse it forBreakawayPrevailViscosityMax tempFixture
222Small screws under 1/4", set screws and adjusters that would shear before a stronger grade let go. Low strength.50 lb·in
6 N·m		35 lb·in
4 N·m		900–1,500 cP300°F20 min†
290Fasteners that are already assembled and torqued, up to 1/2". It wicks into the threads. Also seals porosity in welds and castings.90 lb·in
10 N·m		260 lb·in
29 N·m		20–55 cP300°F20 min†

Sources

Data sheet values are typical test results, not guaranteed specifications. Where a vehicle or component maker names a threadlocker grade for a fastener, follow that. LOCTITE is a registered trademark of Henkel. 41 Designs is not affiliated with Henkel.
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