Drive pins with a .300 head are designed for permanently fastening a fixture to concrete, some types of concrete block, and A36 or A572 structural steel. The pins are formed with a 0.145" diameter shank in various lengths, and a specially designed point to allow proper penetration into typical base materials. Knurled shank designs are available to increase performance in steel base materials. A plastic flute is mounted over the point to retain the drive pin in the fastener guide of the tool providing guidance during the driving operation.Blue Magic pins offer a hard plastic flute for improved centering in the tool and tip protection.