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MCMASTER 3/8-16 SS LOCK NUT

Description & Features

The MCMASTER 3/8-16 SS Lock Nut provides secure fastening effectively preventing loosening caused by vibrations and other forces. Made from stainless steel it is highly resistant to corrosion ensuring durability and reliability in demanding industrial settings.

Designed to fit standard 3/8-16 threads this lock nut guarantees a dependable connection essential for maintaining the integrity of your assembly. Manufactured by McMaster-Carr Supply Co it adheres to rigorous quality standards for consistent performance.

Its robust construction ensures long-term functionality without frequent replacements making it a practical choice for various applications.

MPN: 91831A127

Supplier Part Number: 91831A127

Specifications

Brand Mcmaster-Carr Supply Co	Brand Mcaster-Carr Supply Co	Pack Size 1.00	UOM EA	Supplier Part Number 91831A127	Product Weight 0.05 lbs

Product Questions & Answers (2)

Question by: Janet F on Jun 11, 2025, 8:34 PM

got a bolt that’s 3/8-16. is this lock nut the right match for it?

Answer by: Customer Support on Jun 13, 2025, 10:11 AM

The key is the thread size. This one is made for standard 3/8-16 threads, so it matches a 3/8-16 bolt or stud.

Question by: Glen C on Aug 29, 2025, 12:41 PM

These lock nuts stainless steel all the way through, or just a coating on top?

Answer by: Customer Support on Aug 30, 2025, 3:46 PM

Fully stainless steel construction, not a plated or coated finish. That matters a lot in wet or corrosive environments where a surface treatment would eventually wear through and leave bare metal exposed. McMaster-Carr makes these to hold up in demanding industrial conditions, so you're getting real corrosion resistance throughout the material, not just on the outside.