Device for obscuring lamps for purposes of precaution against air raids

摘要

531,293. Lighting fittings. FASEL, A July 17, 1939, No 20729. Conventior date, July 15, 1938 Addition to 505,705 [Class 75 (ii)] In addition to the disc 7 whose movement expands the plates 6 there is provided a ring 8 which moves with the disc and can be made positively to close the plates. The underside of the disc can be reflecting.