Mutual Screw & Supply

5/16-18 X 4" Machine Screws | Flat Head Slotted Drive | 18/8 Stainless Steel (100 / Pkg.)

5/16-18 X 4" Machine Screws | Flat Head Slotted Drive | 18/8 Stainless Steel - Main image
$65.79 $99.68 In stock

18/8 (304) stainless steel machine screw offering strong corrosion resistance for indoor, outdoor, and washdown environments. Non-magnetic.

Specs

  • Dimensions: 5/16-18 4"
  • Drive type: Slotted
  • Head style: Flat Head
  • Material: 18/8 Stainless Steel
  • Thread: 5/16-18 UNC (coarse)

Features

  • Machine-thread screws for use with nuts or tapped holes
  • Flat head profile
  • Slotted drive
  • 18/8 Stainless Steel construction
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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)

Ryan S. ★★★★★

I was worried about finding slotted screws this size locally, but these fit perfectly into my old machinery’s existing holes. The 304 stainless steel finish feels solid and I’ve got enough for a dozen projects.

Victoria ★★★★★

The flat heads sit flush and clean on my deck rebuild, and the 18/8 stainless seems heavy-duty so far. I’ve been using them in a damp garage with no rust forming, and the coarse threads bite solidly into the wood.

Emily V. ★★★★★

Pulled these out of the pack for a saltwater dock gate and the 18/8 stainless is already holding up better than the old galvanized hardware. The slotted drive seated flush without stripping, even with a wrench snugging the 4-inch length into a thick support.