Specify 5/16-18 x 1/4 18-8 Stainless Steel Hex Head Cap Screw when thread, length, material, and external hex drive must match an existing bill of materials. In this size range it is treated as a hex head cap screw, with the hex head driven by external tooling rather than an internal socket.

Common application reviews include pump bases, flanges, and plant-service hardware. Use it through a clearance hole with a nut or into a prepared tapped hole when the drawing calls for a stainless hex-head fastener.

18-8 stainless steel is an 18% chromium and 8% nickel austenitic stainless material used for ordinary atmosphere, moisture exposure, washdown, and clean appearance. For production, repair, and distributor sourcing, Cold Headers can help confirm the exact diameter and length before quoting.

Technical Highlights

  • Material: 18-8 Stainless Steel
  • Thread Size: 5/16-18
  • Length: 1/4 in.
  • Head Style: Hex
  • Drive: External Hex (wrench or socket driven)
  • Width Across Flats: 0.428-0.438 in.
  • Wrench Size: 7/16 in.
  • Head Height: 0.150-0.163 in.
  • Dimensional Standard: ASME B18.2.1
  • Material Standard: ASTM F593

Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.

Unit of Measure

Specifications

Brands

N/A Cold Headers, Inc.

Diameter

N/A 5/16-18

Length

N/A 1/4 in

Maximum Width Across the Flats

N/A 0.438 in

Minimum Width Across the Flats

N/A 0.428 in

Maximum Width Across Corners

N/A 0.505 in

Minimum Width Across Corners

N/A 0.488 in

Maximum Head Height

N/A 0.163 in

Minimum Head Height

N/A 0.150 in

Material

N/A 18-8 Stainless Steel

Quantity

N/A 100

Package Type

N/A Box

Search

N/A SSHHCMS.5/16-18.1/4

Note

Note

N/A Less Than Package Quantity Specified Plus 25%.