The RGM-40 Kastet (English: Brass knuckles) grenade launcher is a stand-alone version of the Russian GP-30 grenade launcher with a telescoping stock, AK-type pistol-grip and flip-up tangent sights. It is a single-shot muzzle loaded weapon with a self-cocking trigger mechanism and offers a high degree of commonality with the GP-30. It was designed primarily for police use and can use a wide range non-lethal ammunition (e.g., tear gas, stun grenades, etc.). It can also use standard 40mm VOG-25 and VOG-25P fragmentation grenades.
== Users == Russia: Russian Interior Ministry
== See also == RGS-50M – (Russia, Soviet Union): 50mm grenade launcher GM-94 – (Russia) RGSh-30 – (Ukraine) DP-64 – (Soviet Union) BS-1 Tishina – (Soviet Union) RG-6 grenade launcher – (Russia, Soviet Union) M79 Grenade Launcher – (United States) China Lake Grenade Launcher – (United States) HK 69 Grenade Launcher – (West Germany, Germany) HK M320 – (Germany) EAGLE grenade launcher – (Canada) B&T GL-06 Grenade Launcher – (Switzerland) Pallad grenade launcher – (Poland) Fort-600 Grenade Launcher – (Ukraine)