... US G209 rigging shackle 1. manufacturer 2. 3/16, 1/4, 5/16 ,........2-1/2 3. Federal RR-C271DtypeIVB Drop Forged US G209 ... rigging shackle 1. specialized manufacturer 2. 3/16, 1/4 ... , 5/16 ,........2-1/2 3. Federal RR-C271DtypeIVB Nominal size(inches)Working ...