UNF Locknuts | McMaster-Carr

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518 Products

Locknuts

Nylon-Insert Locking About Nylon-Insert Locking

Nylon-Insert Locknuts

Versatile and economical—the most commonly used locknuts

106 products

Thin-Profile Nylon-Insert Locknuts

About half the height of standard nuts to fit in spaces with low clearance

63 products

Thin-Heavy-Profile Nylon-Insert Locknuts

Fit in low-clearance spaces and handle heavier loads than standard nuts

4 products

Mil. Spec. Thin-Profile Nylon-Insert Locknuts

Meet U.S. military standards and are half the height of standard nuts to fit in low-clearance spaces

10 products

Distorted-Thread Locking About Distorted-Thread Locking

Top-Lock Distorted-Thread Locknuts

Irregularly shaped threads at the top grip screws tighter than a nylon insert

80 products

Center-Lock Distorted-Thread Locknuts

Thread on from either side so there’s no risk of damaging screws

21 products

Lock Washer About Lock Washer

Locknuts with External-Tooth Lock Washer

Twist into place by hand to save on assembly time

10 products

Locknuts with Spring-Lock Washer

Grip more tightly than external-tooth washers to better resist vibration

2 products

Cotter-Pin Lockable About Cotter-Pin Lockable

Locknuts for use with Cotter Pins

Secure rotating parts subjected to mild vibration, such as wheels on carts

29 products

Flex-Top Locking About Flex-Top Locking

Flex-Top Locknuts for Heavy Vibration

Stronger hold than nylon-insert and distorted-thread locknuts

25 products

Thin-Profile Flex-Top Locknuts for Heavy Vibration

About two-thirds the height of standard nuts to fit in spaces with low clearance

29 products

Mil. Spec. Flex-Top Locknuts for Heavy Vibration

Meet strict U.S. military standards for material and construction

12 products

Steel-Insert Locking About Steel-Insert Locking

Steel-Insert Locknuts for Extreme Vibration

The most vibration-resistant hold we offer

2 products

Thin-Profile Steel-Insert Locknuts for Extreme Vibration

About two-thirds the height of standard nuts to fit in spaces with low clearance

2 products

Two-Piece-Clamp Locking About Two-Piece-Clamp Locking

Two-Piece-Clamp Locknuts for Extreme Vibration

8 products

Serration Locking About Serration Locking

Serrated Locknuts

Easiest to install but least effective against vibration

1 product

Thread-Forming Lock About Thread-Forming Lock

Thread-Forming Locknuts

Form threads into these nuts for a tight fit that won't loosen under vibration

1 product

Other Products

Flange Nuts

The flange distributes pressure, so you don't need a washer

89 products

Cap Nuts

Cover and protect threads while adding a finished look; also known as acorn nuts

19 products

Thumb Nuts

Easy to tighten and loosen by hand for making frequent adjustments

3 products

Press-Fit Nuts

Push into drilled or punched holes to add threads to thin panels

2 products