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Black oxide flat head socket screws in a small box, 100 pieces

Kerr Lakeside

Kerr Lakeside 1/4-20 x 1/2 in. Flat Head Socket Screw 100 pcs

SKU CH-Q37Y-XCRNT

Pack of 100 alloy-steel flat-head socket screws, 1/4-20 x 1/2 in., black-oxide finish, Rc 38-43 hardness, 180,000 psi tensile strength, ASTM A574/ANSI B18.3 compliant

  • Flat head sits flush in countersunk holes
  • 180,000 psi tensile strength from alloy steel
  • Rockwell hardness Rc 38-43 resists wear
  • Meets ASTM A574 and ANSI B18.3 standards
  • 100-piece pack in compact 1.5 x 1.88 x 3.13 in. box

Flat-head socket screws in bulk

Kerr Lakeside supplies 100 pieces of 1/4-20 by 1/2 inch flat-head socket cap screws. Each fastener is made from alloy steel with a black oxide finish and a Rockwell hardness of 38-43. The coarse UNC thread runs the full half-inch length. They meet ASTM A574 and ANSI B18.3 standards and are RoHS compliant.

Ideal for mechanics and assembly work

These screws suit anyone needing a ready stock of high-strength inch-series fasteners with a hex drive. Buyers who require metric threads, a different head style, or a smaller pack quantity should look elsewhere. The 0.84 lb pack measures 1.5 by 1.88 by 3.13 inches.

Tensile strength rated at 180000 psi

The alloy steel construction delivers a tensile strength of 180000 pounds per square inch, confirming suitability for demanding clamping loads. This single figure decides whether the fastener matches the joint design requirements.

How it compares

Measured against everything we stock in Bits, Hole Saws & Accessory Kits, at today’s prices. Recalculated every night.

Price $14.99
Cheaper than about 77% of the 5,493 comparable items (median $27.99).

Specifications

Product
Brand nameProspect Fastener

Questions about this item

Will these 1/4-20 x 1/2 in. flat head socket screws sit flush in a countersunk hole made for standard ANSI B18.3 hardware?

Yes. The flat head follows ANSI B18.3 dimensions so it seats flush in a standard countersink. The black-oxide alloy steel body meets ASTM A574 and has a Rockwell hardness of RC 38-43.

Can I mix these coarse-thread UNC screws with existing 1/4-20 UNC fasteners in the same assembly?

Yes. They share the same 1/4-20 UNC coarse thread and right-hand thread direction, so they engage identically with existing nuts or tapped holes.

How can I confirm the 100-piece pack contains the correct 1/4-20 x 1/2 in. flat head socket screws after opening?

Each screw shows a 1/4 in. hex drive, flat head, full 1/2 in. thread length and black-oxide finish. The pack weighs about 0.84 lbs and measures 1.5 x 1.88 x 3.13 in.

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