Schlitzblende
Schlitzblende (Ger. slit cover; Abblendkappe), the slotted canvas cover for a vehicle headlight, which reduces the light emission to a narrow slit in the center of the lens. During World War II, these slit covers often became obsolete, because the headlight lenses were simply painted over. The Bosch RL3-40 camouflage device (up to 200 mm) could be mounted on commercially produced civilian headlights.