ZE-116 brass rotary 2-circuit light switch 

3-Way, 4 Position, 2 Circuit Rotary Switch

13/32" (0.40") thread length
6" wire leads
hex nut and knurl nut included

ratings:
6A 125V
3A 250V

when wired:
turn 1 = light 1 (or lights on circuit 1) on - lights on circuit 2 off
turn 2 = light 2 (or lights on circuit 2) on - lights on circuit 1 off
turn 3 = both lights (circuits) on
turn 4 = all off