Material: STEEL Assembled Product Length: 1.5" Grade: AS A574 Finish: BLACK OXIDE Assembled Product Height: 0.5" Assembled Product Width: 0.5" Fastener Diameter (Imperial): 0.5" Fastener Length (Imperial): 1.5" Fastener Length (Metric): 38.1 MM Fastener Diameter (Metric): 12.7 MM . Socket head. Coarse thread. The positive hex drive provides extra torque without stripping the heads of the fasteners