AEG, RPF and Letiz also produced a Zielgeraet or active night-vision device for the Sturmgewehr 44 assault rifle. The ZG 1229 Vampir weighed in at 2.25 kilograms (about 5 lbs.) and was fitted with lugs on the StG 44 at C.G. Haenel at Suhl, the weapons production facility. The grenadier carrying this monster was known as a Nachtjager and carrying this rifle must have been no joy. As well as the sight and spotlight, there was a 13.5 kilogram (about 30 lbs.) wooden cased battery for the Scheinwerfer, and a second battery fitted inside a gas mask container to power the Bildwandler. This was all strapped to a Traggestell 39 (pack frame 39). In Waldemar Trojca's Panther, volume 2, Vampir gear was: "First used in combat in February 1945". However, he later goes on to say: "Small arms infrared device introduction must have taken place in early 1944. Both my late grandfather, Gerhard Sarnes, and one of the ex-soldiers that I interviewed, did recall Eastern Front snipers shooting at night with the aid of 'peculiar non-shinning torches coupled with enormous optical sights' mounted on their rifles. Similar infrared gear was fitted both to MG34 and MG42 machine guns." So there remains a good deal of mystery surrounding these late-war weapons.