guided by two guide rods brazed to it and these rods run inside steel bearings in the receiver. The guide rods are hollow and contain the return springs. The bolt also contains a claw extractor that forms the eighth locking lug and a spring-loaded "bump"-type casing ejector. The gas cylinder is offset to the right side of the barrel and works with one of the two guide rods. The AUG uses a short-stroke piston system where the right guide rod serves as the action rod, transmitting the rearward motion of the gas-driven piston to the bolt carrier. The left-hand rod provides retracting handle pressure when connected by the forward assist and can also be utilised as a reamer to remove fouling in the gas cylinder. The firearm uses a 3-position gas valve. The first setting, marked with a small dot, is used for normal operation. The second setting, illustrated with a large dot, indicates fouled conditions. The third, "GR" closed position is used to launch rifle grenades (of the non-bullet trap type). The AUG is hammer-fired and the firing mechanism is contained in the rear of the stock, near the butt, covered by a synthetic rubber shoulder plate. The hammer group is made entirely of plastics except for the springs and pins and is contained in an open-topped plastic box which lies between the magazine and the buttplate. During firing the recoiling bolt group travels over the top of it, resetting the hammer. Since the trigger is located some distance away, it transmits its energy through a sear lever which passes by the side of the magazine. The firing pin is operated by a plastic hammer under pressure from a coil spring. Features The AUG comes standard with four magazines, a muzzle cap, spare bolt for left-handed shooters, blank-firing adaptor, cleaning kit, sling and either an American M7 or German KCB-77 M1 bayonet. Muzzle devices and barrel lengths A three-pronged, open-type flash suppressor was used on the , and length barrels, whereas the light machine gun barrel received a closed-type ported muzzle device (combination flash suppressor and compensator) and an integral, lightweight folding bipod. The flash suppressors are screwed to the muzzle and internally threaded to take a blank-firing attachment. Trigger The AUG features an Spz-kr type progressive trigger (pulling the trigger halfway produces semi-automatic fire, pulling the trigger all the way to the rear produces fully automatic fire) and