Mutual Screw & Supply

5/16-18 X 3-1/2" Machine Screws | Flat Head Slotted Drive | 18/8 Stainless Steel (100 / Pkg.)

5/16-18 X 3-1/2" Machine Screws | Flat Head Slotted Drive | 18/8 Stainless - Main image
$48.25 $77.82 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 3-1/2"
  • 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)

George ★★★★★

Had to swap out some old screws on a pergola that gets blasted by rain all year, and these 304 stainless ones slid right in without any binding. The 3-1/2 inch length grabbed perfectly through pressure-treated lumber, and the flat head sits flush so nothing snags.

Abigail ★★★★★

Used these for a boat dock repair and the 18/8 stainless is holding up perfectly against the saltwater spray. The slotted heads let me really torque them down without stripping.

Hannah ★★★★★

Installing these in a stainless steel railing project and the 18/8 material feels solid, should hold up well outdoors. The 3-1/2 inch length was exactly what I needed to get through the wood and into the framing.