Mutual Screw & Supply

5/16-18 X 3" Machine Screws | Round Head Slotted Drive | 18/8 Stainless Steel (100 / Pkg.)

5/16-18 X 3" Machine Screws | Round Head Slotted Drive | 18/8 Stainless Steel - Main image
$43.93 $61.88 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 3"
  • Drive type: Slotted
  • Head style: Round Head
  • Material: 18/8 Stainless Steel
  • Thread: 5/16-18 UNC (coarse)

Features

  • Machine-thread screws for use with nuts or tapped holes
  • Round head profile
  • Slotted drive
  • 18/8 Stainless Steel construction
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Standard Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

Express Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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Returning an item

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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 (5.0 / 5 · 5 reviews)

Timothy H. ★★★★★

I picked these for a heavy-duty outdoor project where corrosion resistance was a must, and the 18/8 stainless steel has held up perfectly through a few rainstorms. The 3-inch length gave me just the right grip for fastening into pressure-treated lumber.

William E. ★★★★★

The slotted heads on these 5/16-18 screws bit nicely into my driver without slipping, and the stainless steel feels solid for outdoor use. Perfect length for securing some heavy brackets on the deck.

Jacob ★★★★★

Finally, a machine screw that doesn't rust after a season outdoors—the 18/8 stainless finish has held up perfectly on my gate hinges through all the rain. The 3-inch length gave me just enough thread engagement for a solid grip, and being non-magnetic made handling them a breeze.