Estimated era 50-70's uses standard 6 volt spring top, very similar to the RavOvac's and Bigbeams from the same time frame, standard 4.75 volt .5 amp bulb will give you around 2.375 watts with about 47 lumens on fresh batteries. With a big reflector like that expect good throw "over 12,000 Lux" but with tons of artifacts and dim side-spill. With a normal heavy duty battery you should get about 26 hours of run time "though after the first 3 hours the light will be much dimmer". Value approximately between $10 and $15 "unless it is a rare model, to be fair I've never seen this particular light but they made TONS of lights like this back in the day:thumbsup:.