Mutual Screw & Supply

#4-40 X 5/16" Machine Screws | Flat 100° Head Phillips Drive | 18/8 Stainless Steel Black Oxide (1800 / Pkg.)

#4-40 X 5/16" Machine Screws | Flat 100° Head Phillips Drive | 18/8 Stainless - Main image
$12.67 $19.8 In stock

These #4-40 x 5/16" machine screws are manufactured from 18/8 Stainless Steel with a black oxide finish, featuring a phillips drive and a flat 100 head. They are well suited to fastening metal parts, panels, and enclosures.

  • Material and finish: 18/8 Stainless Steel, Black Oxide finish
  • Drive: Phillips
  • Head style: Flat 100
  • Thread size: #4-40
  • Length: 5/16"
  • Applications: Fastening metal parts, panels, and enclosures

Specifications

  • Product type: Machine Screws
  • Material: 18/8 Stainless Steel
  • Finish: Black Oxide
  • Grade: 18/8
  • Head style: Flat 100
  • Drive type: Phillips
  • Thread size: #4-40
  • Length: 5/16"
  • Threads per inch: 40
  • Measurement type: Imperial
  • Pack quantity: 100 per package

Please note: This item is excess stock and is sold non-cancelable, non-refundable, and non-returnable. Please call us with any questions about this item before ordering.

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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.8 / 5 · 5 reviews)

Hannah ★★★★★

Was a bit worried the 100° flat head wouldn't sit flush in my aluminum brackets, but they countersink perfectly and the black oxide finish looks great against the dark metal. Exactly the right size for #4-40 threaded holes.

Stella N. ★★★★★

Took a chance on the 18/8 stainless with black oxide finish for a project and the 100° flat head sits perfectly flush in the countersunk holes. The 1800 count means I'll have backups for years, and the phillips drive didn't strip once even on the tighter threads.

Emily ★★★★★

Used a handful to secure a small metal bracket and the 100° flat head sat perfectly flush. The 18-8 stainless with black oxide feels tough and should resist corrosion well.