Leviton Available 7090-PG Medium Base Complete, Aluminum Shell Incandescent Lampholder, Removable Turn Knob, 2-Circuit, for 3-Way 2-Filament Lamps, Brass, 1 Pack Metal shell lampholder Medium base Removable turn knob 2-circuit, sequence Low-Medium-High-Off 1/8 IPS Tapped Bushing w/Set Screw