Mutual Screw & Supply

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

5/16-18 X 4" Machine Screws | Flat Head Slotted Drive | Plain Steel (100 / Pkg.) - Main image
$33.27 $46.21 In stock

Plain (uncoated) steel machine screw for general-purpose, indoor fastening where corrosion resistance is not required.

Specs

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

Features

  • Machine-thread screws for use with nuts or tapped holes
  • Flat head profile
  • Slotted drive
  • Plain 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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Delivery costs

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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 (4.6 / 5 · 5 reviews)

Harper ★★★★★

These slotted heads feel like they were cut cleanly, so my screwdriver actually bites without slipping. I used them to assemble a heavy workbench frame and the 4-inch length grabbed perfectly through thick lumber. Exactly the solid, no-frills fastener I needed for indoor shop projects.

Kevin ★★★★★

Finally, a machine screw that’s actually 4 inches long when it arrives, not a hair short. The flat head sits flush in my counterbore without any wobble, and the slotted drive bites cleanly with a standard screwdriver. Plain steel is perfect for my indoor jig since rust isn’t a concern here.

Chloe ★★★★★

Needed a few for a workbench project and these 5/16-18 x 4” slotted screws worked perfectly with a countersink bit. The plain steel finish is fine for indoor use and they threaded smoothly into my pre-drilled holes.