Mutual Screw & Supply

5/16-18 X 3-1/4" Machine Screws | Round Head Slotted Drive | Steel Zinc Plated (100 / Pkg.)

5/16-18 X 3-1/4" Machine Screws | Round Head Slotted Drive | Steel Zinc Plated - Main image
$38.32 $55.54 In stock

Zinc-plated steel machine screw for general-purpose fastening. The zinc coating adds corrosion resistance for indoor and light outdoor use.

Specs

  • Dimensions: 5/16-18 3-1/4"
  • Drive type: Slotted
  • Head style: Round Head
  • Material: Steel Zinc Plated
  • Thread: 5/16-18 UNC (coarse)

Features

  • Machine-thread screws for use with nuts or tapped holes
  • Round head profile
  • Slotted drive
  • Steel Zinc Plated construction
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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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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)

William ★★★★★

I was a little worried the slotted head would be tough to work with, but they bite into the wood perfectly and the zinc coating hasn't shown any rust yet after a few weeks on the porch railing.

William K. ★★★★★

Got these for a metal bracket project and the zinc coating is holding up well in my damp garage. The slotted heads drive in cleanly with a standard screwdriver.

Jason Y. ★★★★★

I needed a longer 5/16-18 screw for a project and these 3-1/4" ones worked perfectly. The zinc plating seems consistent across all 100, so they should hold up fine for light outdoor use.