The HK53 is the ultra-compact submachine-gun-sized variant of the HK33 family, fitted with an 8.85-inch barrel. Despite its small size, it fires the full 5.56x45mm rifle cartridge rather than a pistol cartridge, blurring the line between PDW and assault rifle. Used by German border police, GSG-9, and special operations units. Type: Rifle Action: Semi/Full-Auto Caliber: 5.56x45mm Capacity: 25 Year introduced: 1975, Germany Weight: 94.4 oz Overall length: 14.7" Status: Discontinued Military use: Yes Intended use: special_operations, law_enforcement