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Zoro Select

Zoro Select MPB657 Hex Nut 3/8-24 Steel Grade 2 Chrome 21/64 in

SKU CH-TZ85-D99BG

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

BrandZORO SELECT
TypeNuts
Size3/8-24

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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