Thread Size: 1/2-13; Thread Pitch: 13 TPI Coarse Thread Full Thread Coverage; Bolt Thread Length: 1.75 inch Hex Wrench Size: 3/4 inch; Package Contents: 6 Sets (bolts + matched nuts, flat washer and lock washer) Material: The sets are all made of 304 stainless steel 18/8; Excellent toughness; Good rust and corrosion resistance in both indoor and outdoor use; Extra Black Oxide treatments make it more chemical resistance while not impact strength or hardness Feature: (1) Can be easily tightened by standard wrenches; (2) Withstand heavy vibrations and impacts for machinery usage; (3) Resist loosening over time; (4) Black Coating will not easily wear off over time; (5) Widely used in home improvement and industry applications due to their versatility and strength, their sturdy design ensure a secure connection Fastener Standard: Hex Bolt meets standard ANSIB 18.2.1; Hex Nut meets standard ANSIB 18.2.1; Flat Washer meets standard ANSIB18.22.1SAE; Lock Washer meet standard ANSIB18.21.1