The Glock 21 Gen3 SF is the Short Frame variant on the Gen3 platform, introduced before the Gen4 combined SF functionality with the full fourth-generation improvements. The Gen3 SF reduced trigger reach from 2.84 to 2.76 inches on the Gen3 frame profile, making the full-size .45 ACP accessible to smaller-handed shooters a generation before the standard Gen4 SF was available. Type: Pistol Action: Semi-Automatic Caliber: .45 ACP Capacity: 13 Year introduced: 2007, Austria Weight: 26.28 oz Overall length: 8.22" Status: Discontinued Intended use: Law Enforcement, Self-Defense