Would this be 2 heavy for gun sight installation or just what i need?

It might be to much for 271. It was designed for larger treads 3/8 + hold, and might make it impossible to remove at a latter time because of inability to apply enough heat and torque to remove from small treads like a scope mount. use Blue which is for small threads

Does this product require a primer? The fourth picture on Amazon suggests it does but the instructions do not mention a primer. Stainless + aluminum

I didn't need to. I used it on steel threads. Didn't even clean them. Applied this product and assembled. Hardened in minutes. I waiyed 24hrs before use just in case. Excellent product. I've used in the automobile repair industry for 30yrs.

Would this be appropriate for the locking nut on a sink faucet, that is always coming loose and making the faucet wobble?

Oh god no! This is for applications of extreme vibration and areas that's could be extremely dangerous if a bolt or nut came loose. All you should need for you faucet is the blue loctite. After using the red, you would need some serious heat and a breaker bar to free that nut if you needed to replace that faucet in the future.

if it is opened/used, how long will it stay fresh/usable?

Unopened/opened shelf life of Loctite 271 is two years from date of manufacture. Since exposure to oxygen is what keeps the liquid product stable, and it is packaged in a "breathable" plastic bottle, there is no change in shelf life once the product has been opened.

Fully operational. Shipping worldwide, on schedule.Duty & taxes paid at delivery

Help Track order

Account Cart

Fully operational. Shipping worldwide, on schedule.Duty & taxes paid at delivery

Help Track order

Account Cart

Loctite 37421 271 Red Heavy Duty Threadlocker, 6-Milliliter Tube

Product ID: 298827944

Details

Brand
Loctite
Item Form
Tube
Material
Metal-based
Special Feature
Strong
Specific Uses For Product
Automotive DIY

🔥Heat resistant up to 140°F

🔩High-strength bond for heavy-duty bolts

⏱️Sets in 10 minutes, full cure in 24h

Buy anything from 5,000+ international stores. One checkout price. No surprise fees. Join 2M+ shoppers on Desertcart.

€ 46.98

Duties & taxes included

In stock

Sold byAmazon CroatiaDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Croatia.

Secure transaction

Description

🔧 Lock it down like a pro — don’t let your bolts bail on you!

EASY DISASSEMBLY - Requires only localized heating and hand tools for hassle-free maintenance.
RAPID INITIAL SET - Starts curing in just 10 minutes to keep your project moving fast.
EXTREME DURABILITY - Engineered to withstand heavy shock, vibration, and harsh chemical environments without fail.
ALL METAL COMPATIBILITY - Works flawlessly on stainless steel, aluminum, and plated surfaces—even with minor oil presence.
PROFESSIONAL GRADE STRENGTH - Trusted by OEMs and pros for securing large bolts and studs over 1 inch.

LOCTITE 37421 Red Heavy Duty Threadlocker is a professional-grade adhesive designed for large bolts and studs, delivering a rapid 10-minute set and full strength in 24 hours. Trusted by automotive OEMs and professionals, it bonds to all metals including stainless steel and aluminum, tolerates minor oil contamination, and resists shocks, vibrations, and temperatures up to 140°F. Ideal for heavy-duty automotive and industrial applications, it ensures durable, reliable fastening with easy disassembly when needed.

Specifications

ASIN	B0028OJAIY
Brand	Loctite
Brand Name	Loctite
Colour	Red
Compatible Material	Aluminium
Container Type	Tube
Country of Publication	USA
Customer Reviews	4.8 out of 5 stars 1,042 Reviews
Full Cure Time	24 Hours
Global Trade Identification Number	00079340374218
Included Components	(1) LOCTITE 271 Threadlocker for Automotive \| Red, 6 ml Tube
Item Form	Tube
Item Package Quantity	1
Item Type Name	Loctite 487232 Threadlocker 271 High Strength Tube, Red, 6-ml
Item Weight	5 g
Manufacturer	Loctite
Manufacturer Part Number	37421
Material	Metal-based formulation
Material Type	Metal-based formulation
Model	37421
Number of Pieces	1
Other Special Features of the Product	Strong
Special Feature	Strong
Specific Uses For Product	Automotive, Industrial, DIY, Furniture, Heavy-Duty
UPC	079340374218
Viscosity Level	Low
Volume	6 Millilitres
Water Resistance Level	Water Repellent

Reviews

D**É

Efficacité

Filetage adapteur pour moteur

7.08.2023

J**.

Buena compra

Rinde mucho y es un producto y marca que cumple lo que promete

20.06.2022

A**M

Works

Love the lock and unlock tip and work good as well

9.08.2025

N**S

Did the job perfectly

Replacing axle nuts on my ‘06 Corvette. Locked them on the shaft easily. As recommended, waited 24 hours for the thread lock to set properly.

5.08.2022

J**J

buena calidad

Llega a tiempo y Excelente producto

13.04.2022

Common Questions

Are the products genuine and authentic?+

Yes, all products are sourced directly from authorized retailers in the US, UK, UAE and India. We maintain strict quality control processes and verify each product before shipping. All items come with applicable manufacturer warranties and are covered by our standard return policy.

How long does delivery take and is it reliable?+

Delivery times vary by destination country, typically ranging from 3-9 business days. Each order is fully trackable through our system. We handle all customs clearance and use reliable courier partners for last-mile delivery. You'll receive regular updates about your order status via email and our app.

What is Desertcart? Is it safe to order from?+

Desertcart is an international e-commerce platform operating since 2014. We securely process thousands of orders globally each day. Every product goes through our quality verification process before delivery, and we provide end-to-end order tracking, 24/7 customer support, and a comprehensive returns policy to ensure a safe shopping experience.

How is product pricing calculated?+

Our prices include the product cost, international shipping, import duties, customs clearance, and local delivery charges. We handle all customs and import procedures, ensuring there are no hidden fees upon delivery. PRO members receive additional benefits including free shipping.

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Ayesha M.

The product exactly matches the description. Very satisfied with my purchase.

5 days ago

Suresh K.

Very impressed with the quality and fast delivery. Will shop here again.

4 days ago

View all Trustpilot reviews

Shop Global, Save with Desertcart

Value for Money

Competitive prices on a vast range of products

Shop Globally

Serving millions of shoppers across more than 100 countries

Enhanced Protection

Trusted payment options loved by worldwide shoppers

Customer Assurance

Trusted payment options loved by worldwide shoppers.

Desertcart App

Shop on the go, anytime, anywhere.

Buy anything from 5,000+ international stores. One checkout price. No surprise fees. Join 2M+ shoppers on Desertcart.

€ 46.98

Duties & taxes included

In stock

Sold byAmazon CroatiaDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Croatia.

Secure transaction

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Sneha T.

Received my product in pristine condition. Great service overall.

1 month ago

Zainab N.

Fantastic and great service. Shipping was faster than expected.

1 week ago

View all Trustpilot reviews