Cone  " diabolo " swing arm wall light by Rene Mathieu for Lunel, France 1950, original dark red ( grenat )  colored enameled metal shade with decorative star perforations on an articulate brass arm and custom brass backplates, wired for US standards, fitted with a  bayonet  bulb ( original brass socket,bulb provided as a onetime courtesy, bayonet lamp  can be found on Amazon  (readily available under Light Bulb Vintage Bayonet Lamp).
Robert Mathieu (1921-2002) is one of the most talented creators and producers of French lighting from the 1950’s. He frequented the Boulle school of applied arts before beginning a career as a clockmaker in 1938. In 1949 he debuted his creations at 98 boulevard Charonne which would remain his flagship store. His first pieces rivaled ingenuity and were marked by his initial training in clock making.
Reflector D. 8 in x L.8.5 In , arms 11 in each , fully open 22 in + reflector . Bayonet original socket 
I can be reach at the 310 994 6009 if you want more info on condition  , for shipping outside the US please contact me for pricing and condition