Key Specs: Thread & Length 1/4-20 x 3/4"; Head Diameter: 0.48"~0.53" (12.2-13.48mm); Drive Type: 5/32" Hex Socket; Package: 25 PCS 304 Stainless Steel with a Durable Black Coating; Offers superior corrosion resistance and strength for harsh environments; Resists high heat, freezing temperatures, and humidity with zero maintenance; The fade-resistant black finish maintains its look over time Secure Hex Socket Drive: The internal hex (Allen) drive provides superior torque transfer compared to Phillips or slotted drives, significantly reducing cam-out and tool slippage. This allows for tighter, more reliable installations and easier removal even after prolonged use The 82-degree (standard) countersunk head is engineered to sit perfectly flush or below the surface in pre-drilled countersink holes. This creates a smooth, unobtrusive finish ideal for machinery, fabrication, automotive work, and DIY projects where a clean profile is required This coarse-thread size is widely used in structural fabrication, trailers, lifting equipment, and public infrastructure. The black finish enhances its suitability for architectural metalwork, fitness equipment, truck bed accessories, and industrial shelving that demands high strength, a flush surface, and extra corrosion protection 1/4-20 x 3/4" Flat Head Socket Head Cap Screws Black, Allen Hex Drive, 304 Stainless Steel 18-8, Black Coated Finish, Corrosion Resistant, Full Thread, Coarse Thread, 25 PCS