Zoro Select
Zoro Select MPB657 Hex Nut 3/8-24 Steel Grade 2 Chrome 21/64 in
A chrome-plated Grade 2 steel hex nut with 3/8-24 fine threads, 9/16 in hex width and 21/64 in height, sold in a 50-piece pack
- TypeNuts
- Size3/8-24
- Chrome-plated steel resists corrosion in everyday use
- Fine 3/8-24 thread fits precision fastening tasks
- Grade 2 rating meets ASME B18.2.2 and SAE J995 standards
- 21/64 inch hex height works with standard 9/16 inch wrenches
- Pack of 50 supplies multiple jobs from one box
Threaded Fastener
The Zoro Select MPB657 is a standard hex nut designed for mechanical assemblies requiring a 3/8"-24 fine thread. It suits maintenance technicians and fabricators who need a reliable Grade 2 steel fastener with a chrome-plated finish for corrosion resistance.
Fine Thread Specification
The single specification that determines fit is the 3/8"-24 thread size with a 2B thread fit and right-hand direction. This fine pitch distinguishes it from coarse-thread alternatives and must match the mating bolt or stud exactly for proper engagement.
Assembly Integration
The nut features a 9/16 in hex width for standard wrench access and a 21/64 in height. It conforms to ASME B 18.2.2 dimensional standards and SAE J995 material quality standards. Supplied in a 50-piece pack, it provides a removable fastening solution for inch-system hardware builds.
Highlights
- Chrome-plated steel resists corrosion in everyday use
- Fine 3/8-24 thread fits precision fastening tasks
- Grade 2 rating meets ASME B18.2.2 and SAE J995 standards
- 21/64 inch hex height works with standard 9/16 inch wrenches
- Pack of 50 supplies multiple jobs from one box
Specifications
| Brand | ZORO SELECT |
|---|---|
| Type | Nuts |
| Size | 3/8-24 |
Questions about this item
What does the 3/8-24 thread size mean when I install this nut?
It indicates a 3/8 inch diameter with 24 fine threads per inch, matching SAE fine-thread bolts or studs of the same specification.
What does the Grade 2 and ASME B 18.2.2 standard cap in practice?
Grade 2 steel sets the mechanical strength level, while ASME B 18.2.2 governs the nut's dimensions and 2B thread fit for interchangeability.
What clearance does the 9/16 inch hex width and 21/64 inch height need to fit?
A 9/16 inch wrench or socket fits the hex flats, and the nut stands 21/64 inch tall, so allow that height above the mounting surface.
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