The G37 Gen3 introduced the .45 GAP (Glock Automatic Pistol) cartridge, designed by Glock and Ernest Durham of Speer to provide .45 ACP ballistics in a cartridge short enough to fit a standard-frame pistol. The G37 uses the full-size G22-dimension frame rather than the wider G21 frame. Type: Semi-Automatic Pistol Action: Striker-Fired Caliber: .45 GAP Capacity: 10 Year introduced: 2003, Austria Weight: 27 oz Overall length: 7.32" Status: Discontinued Intended use: law enforcement, duty, service, defense