Closed Spelter Sockets Cast Spelter Sockets meet the requirements of ASTM A148/A148M-84 Gr 90/60. Spelter Socket Pins meet the requirements of ASTM A322-82 Gr 4140. Cast Spelter Sockets are recommended for use with 6x7, 6x19, 6x37, EIP, RRL, FC or IWRC, wire rope or strand. Design Factor is 5:1. Sockets L-7000 to L-7007 are supplied with grooves. Grooves in larger sockets supplied by special request only. Spelter Sockets are available painted or galvanized.