Screw-in dimmer allows you to quickly and easily convert any lamp into a 3-way touch lamp. After the unit is installed, you can touch any metal part to activate the lamp. Helps you save energy and extend bulb life. Use with metal socket lamps. Maximum wattage is 150. 3-way touch lamp. Saves energy. Extend bulb life. Use with metal socket lamps. Maximum wattage is 150.