unbrako Bolt 400056  (Allen Bolt Size,3/16*3/8 Inch (Alloy Steel))

Deep accurate socket for high torque wrenching. Knurls for easier handling. Marked for easier identification. Head with increased bearing area for greater loading carrying capacity. Precision forged for symmetrical grain flow maximum strength. Elliptical fillet doubles fatigue life at critical head-shank juncture. “3-r” (radiused-root runout) increases fatigue life in this critical head-shank juncture. Controlled heat treatment produces maximum strength without brittleness. Accurate control of socket depth gives more wrench engagement permits full tightening without cracking or reaming the socket yet provides ample metal in the crucial fillet area for maximum head strength. Contour-following lines provide extra shear strength and provide high fatigue resistance.