Stiff Nuts | McMaster-Carr

Filter by

System of Measurement

Thread Size

Nut Type

Locking Type

Material

Finish

Cadmium Yellow-Chromate Plated

Corrosion-Resistant Coated

Zinc Yellow-Chromate Plated

Hex Nut Profile

Height

Fastener Strength Grade/Class

Width

Thread Pitch

Thread Type

Performance

Thread Direction

Thread Spacing

Fastener Strength Rating

Specifications Met

Thread Fit

Unified Standard Class 2B

Unified Standard Class 3B

DFARS Specialty Metals

Compliant

Exempt

Not Compliant

Distorted Thread Type

Center Lock

Top Lock

RoHS

Compliant

Compliant with Exemptions

Not Compliant

REACH

Compliant

Not Compliant

Export Control Classification Number (ECCN)

EAR99

Sold As

Assortment

Individual

Insert Maximum Temperature

Flange Diameter

1,745 Products

Locknuts

Nylon-Insert Locking About Nylon-Insert Locking

Nylon-Insert Locknuts

Versatile and economical—the most commonly used locknuts

468 products

Thin-Profile Nylon-Insert Locknuts

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

164 products

Heavy-Profile Nylon-Insert Locknuts

About 10% wider and taller than standard nuts to handle heavier loads

31 products

High-Profile Nylon-Insert Locknuts

Larger gripping area keeps wrenches from slipping off as you tighten

49 products

Thin-Heavy-Profile Nylon-Insert Locknuts

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

33 products

Mil. Spec. Nylon-Insert Locknuts

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

21 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

17 products

Nylon-Insert Locknut Assortments

A range of sizes to fasten a variety of parts

2 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

285 products

Center-Lock Distorted-Thread Locknuts

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

86 products

Left-Hand-Thread Center-Lock Distorted-Thread Locknuts

Secure parts that rotate counterclockwise, such as the propeller on a mixer

6 products

Flex-Top Locking About Flex-Top Locking

Flex-Top Locknuts for Heavy Vibration

Stronger hold than nylon-insert and distorted-thread locknuts

87 products

Thin-Profile Flex-Top Locknuts for Heavy Vibration

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

58 products

Heavy-Profile Flex-Top Locknuts for Heavy Vibration

About 10% wider and taller than standard nuts to handle heavier loads

13 products

Thin-Heavy-Profile Flex-Top Locknuts for Heavy Vibration

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

9 products

Mil. Spec. Flex-Top Locknuts for Heavy Vibration

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

18 products

Steel-Insert Locking About Steel-Insert Locking

Steel-Insert Locknuts for Extreme Vibration

The most vibration-resistant hold we offer

16 products

Thin-Profile Steel-Insert Locknuts for Extreme Vibration

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

9 products

Heavy-Profile Steel-Insert Locknuts for Extreme Vibration

About 10% wider and taller than standard nuts to handle heavier loads

19 products

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

Two-Piece-Clamp Locknuts for Extreme Vibration

8 products

Spring-Stop Locking About Spring-Stop Locking

Spring-Stop Locknuts

Withstand heavy vibration similar to distorted-thread nuts and are reusable

10 products

Other Products

Flange Nuts

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

209 products

Cap Nuts

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

79 products

Weld Nuts

Weld to metal surfaces to add permanent threads

22 products

Press-Fit Nuts

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

17 products

Thumb Nuts

Easy to tighten and loosen by hand for making frequent adjustments

8 products

Push Nuts

Press onto threads for a light duty hold that’s faster to install than typical nuts

1 product