.45 ACP. 3.9" barrel length. SN: 51B012936. Nitron finish to slide with Matte anodized to alloy frame and one-piece black synthetic grips. Short-recoil operated DA/SA autoloading pistol fed by detachable double-stack magazines. Mounts triple dot Tritium night sights. Standard markings include SIG SAUER P227 SAS to left slide with SIG SAUER/CUSTOM SHOP marking engraved on the right. Lacks magazine. {MODERN}