SIG SAUER Cal-x Kit Sigmcx 5.56 - WCALX-MCX-556N-11B-LT. 56 11.5" Pistol Specifications for SIG SAUER Cal-x Kit Sigmcx 5.56: Manufacturer: SIG SAUER Magazine Capacity: 0 Round Package Contents: SIG SAUER Cal-x Kit Sigmcx 5.56