1.U,S type open spelter sockets 2.Spelter Socket,Open Type Spelter Socket,Rigging,Hardware 3.Material: Mild steel Grooved Open Spelter Sockets: * ... OR XIP,XXIP(EIP),RRL,FC,OR IWRC wire rope. Open Grooved Scokets meet the performance requirements of Federal Specificatioin RR ... -S-550D,Type A, except for those provisions required of ...