Mutual Screw & Supply

5/16-18 X 3-1/2" Machine Screws | Flat Head Slotted Drive | Plain Steel (100 / Pkg.)

5/16-18 X 3-1/2" Machine Screws | Flat Head Slotted Drive | Plain Steel (100 / - Main image
$25.2 $38.77 In stock

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

Specs

  • Dimensions: 5/16-18 3-1/2"
  • 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 · 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)

Matthew S. ★★★★★

These are the exact length I needed for a few heavy brackets; the 3-1/2" flat head sits perfectly flush in the countersunk hole. The slotted drive grabbed my screwdriver nicely without any cam-out. Exactly what you'd expect from a solid steel machine screw.

Ruby ★★★★★

Slotted head on these 5/16-18 machine screws made it easy to get good torque with a standard flathead screwdriver. Exactly 3-1/2 inches long, which worked perfectly for a furniture repair where I needed a bit more reach. Plain steel is fine for my indoor shop jig.

Aurora ★★★★★

I needed a longer fastener for a jig I was building, and these 3-1/2" slotted flat heads threaded in smoothly without any binding. The plain steel finish looks standard, which is fine for my indoor shop project.