iexcell 1/4-20 x 3-1/2″ Hex Socket Cap Screw Bolt

✔ 1 Pcs Hex Key, Hex Size: 3/16, to Drive These Screws Conveniently and Easily. ✔ Material of Screws: Alloy Steel 40Cr, Black Oxide Finish; Strength Grade of Screws : 12.9 Grade, Hardness: HRC 39-44, Tensile Strength: 1220 N/mm².