The "RPG's" shown are actually AT-4 recoilless rocket launchers (RCL), which technically are not RPG (rocket propelled grenade) launchers. A true RPG will have considerable recoil when fired, whereas an RCL will eject highly pressurized gas from the rear of the launcher at the exact moment of firing in order to create forward thrust to counteract the recoil created by the rocket firing. Also an RPG is designed to be able to be reloaded and fired multiple times, whereas the AT-4 (and most RCL's) are designed to be a single use, disposable rocket launcher.