The HK4 in .22 LR provides an economical training variant of the same form factor using a direct blowback action appropriate for the rimfire cartridge. Conversion kit approach allowed agencies to train with .22 LR and qualify with .32 or .380 ACP using the same pistol frame. Type: Pistol Action: Semi-Automatic Caliber: .22 LR Capacity: 8 Year introduced: 1967, Germany Weight: 18 oz Overall length: 6" Status: Discontinued Intended use: range, training, concealed_carry