What is Loctite 661 used for?

You use it to bond cylindrical metal parts such as gears, bearings, bushings, and rotors onto shafts.

How does this retaining compound cure?

It cures anaerobically in the absence of air between metal surfaces and also cures with exposure to UV light.

What is the maximum gap size it can bridge?

Loctite 661 accommodates a maximum diametral clearance of 0.15 mm.

What is the operating temperature range?

This compound resists service temperatures ranging from -55 °C to +175 °C.

How do you disassemble parts bonded with Loctite 661?

Due to its high strength, disassembly requires applying localized heat and using standard hand tools.

LOCTITE 661 strong adhesive for cylindrical fixing (250 ml bottle) - 195783

Name: LOCTITE 661 strong adhesive for cylindrical fixing (250 ml bottle) - 195783
Brand: LOCTITE
SKU: 02621538
Price: 326.2 EUR
Availability: PreOrder

Supplier number: LOCTITE 195783 | EAN 5010266661612

Recommended Retail Price €412.21

326.20 tax incl.

€269.59 excl. VAT (incl. all environmental contributions)

On order: delivered from 29/10/2026

Ordered before 20:00 - delivered as of 29/10/2026
Free shipping
Delivery by DHL
Delivered from Belgium

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How does it work?

For a purchase value of €99 to €125 excl. VAT, receive FREE LOCTITE 55 thread sealing cord 50 m (IDH 528244) worth €9.99.
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The promotion is valid from 01.10.2026 to 31.10.2026.
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Reliable cylindrical assembly with Loctite 661

Practical benefits

High strength cylindrical retention: You secure gears and rotors onto shafts with high load-bearing strength built for demanding mechanical environments.
Resists shock and vibration: The liquid compound fills gaps completely, helping you prevent loosening and leakages caused by continuous operational movement.
Dual curing mechanism: It cures in the absence of air between metals or under UV light so you achieve fast fixture times.

In a nutshell

The right choise for

With Loctite 661, you achieve a high-strength, durable bond for cylindrical metal components. This liquid retaining compound is specially designed for securing bearings, bushings, gears, and rotors onto shafts subjected to heavy mechanical loads. By completely filling clearances up to 0.15 mm, it prevents fretting corrosion, slippage, and loosening caused by severe shock and vibration. The dual-cure system works anaerobically between fitted metal surfaces and reacts to uv light for fast, controlled fixturing. Resisting operating temperatures from -55 °C to +175 °C, this 250 ml bottle delivers dependable retention for demanding industrial assembly and maintenance jobs.

Product information FAQ

€326.20

tax incl.

Key features according to our expert

Net volume: 250 ml
ADR packing group: Not applicable
ADR class: Not applicable
Principal hazard property: GHS05 Corrosive
UN number: Not applicable
P-statements: P261; P273; P280; P302 + P352; P305 + P351 + P338; P333 + P313
H-statements: H315; H317; H318; H335; H412
Hazard class: GHS05 Corrosive; GHS07 Harmful or irritant
Physical state: Liquid
Flash point: > 100 °C

Product description:

LOCTITE 661 is an amber, anaerobic low viscosity, high strength adhesive that also cures in the presence of UV light.
It's therefore ideal for applications where any migration of the adhesive from the joint must be prevented.
Fixture time on steel is 4 minutes and maximum diametrical clearance is >.15mm.
Service temperature is -55°C to 175°C.

Precautionary statements

P261: Avoid breathing dust/fume/gas/mist/vapours/spray.
P273: Avoid release to the environment.
P280: Wear protective gloves/protective clothing/eye protection/face protection.
P302 + P352: IF ON SKIN: Wash with plenty of water/…
P305 + P351 + P338: IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
P333 + P313: If skin irritation or rash occurs: Get medical advice/attention.

Hazard statements

H315: Causes skin irritation.
H317: May cause an allergic skin reaction.
H318: Causes serious eye damage.
H335: May cause respiratory irritation.
H412: Harmful to aquatic life with long lasting effects.

All Features

Net volume: 250 ml
Adr packing group: Not applicable
Adr class: Not applicable
Principal hazard property: GHS05 Corrosive
Un number: Not applicable
P-statements: P261; P273; P280; P302 + P352; P305 + P351 + P338; P333 + P313
H-statements: H315; H317; H318; H335; H412
Hazard class: GHS05 Corrosive; GHS07 Harmful or irritant
Physical state: Liquid
Flash point: > 100 °C

Brand LOCTITE
02621538
EAN 5010266661612
Supplier number LOCTITE 195783

Frequently asked questions about this product

Answered by specialists

What is Loctite 661 used for?: You use it to bond cylindrical metal parts such as gears, bearings, bushings, and rotors onto shafts.
How does this retaining compound cure?: It cures anaerobically in the absence of air between metal surfaces and also cures with exposure to UV light.
What is the maximum gap size it can bridge?: Loctite 661 accommodates a maximum diametral clearance of 0.15 mm.
What is the operating temperature range?: This compound resists service temperatures ranging from -55 °C to +175 °C.
How do you disassemble parts bonded with Loctite 661?: Due to its high strength, disassembly requires applying localized heat and using standard hand tools.