The Sig Sauer M17 CO2 Pistol is a full scale replica of the next US Army Pistol, the M17. Starting our as the Sig P320, the US Army selected the full sized firearm this CO2 pistol is based on to replace the existing M9 pistol. With full 1:1 scale dimensions that match the live firing M17, this air pistol is an excellent way to train for those who carry an M17 or shoot their M17 competitively.