Cm columbus mckinnon SEPTLS490M646G All shackle bodies and pins are forged from alloy steel, heat treated and tempered. All shackles are marked with size (inches and millimeters) and working load limit in tons. Ultimate strength equals 5 times working load limit. Bolt, nut & cotter shackles have thread protected ends and are 100% proof tested. Painted shackles are orange. Standard industry tolerances apply. Built-in Distortion Detectors (3/8 - 2). When ordering, specify galvanized (G) or painted (P).