Knife Switch Double

A brass C.P. spring arm with press knob & two brass terminals. All mounted on bakelite base 80 x 55 mm.

A simple dynamo model to differentiate AC from DC. Mounted on a wooden base. Two bulbs are provided for AC & DC current(s). The model is hand driven & when operated, the AC bulb shows flickering light to indicate AC current while the other bulb glows fully indicating DC current.