Square Head Bolts
ASTM A307 Grade A Square Head Bolts are a low or medium carbon steel, externally threaded bolt, 1/4" diameter or larger, with a trimmed square shaped external wrenching head.
Square head bolts were the industry standard prior to hex bolts taking over. Square head bolts are now normally used in rustic look applications. One advantage is they do offer a greater bearing surface for wrenching than regular hex head bolts.
At RC Fasteners & Components, we stock square head bolts from 1/4" to 1" in diameter and up to 12" in length.