HOW TO CHOOSE BUTTON: For better fitting, you should choose the SHORT/2inch or the LONG/2.5inch button depending on the thickness of your countertop. In most cases, SHORT is for a stainless steel sink top and LONG is for thick countertop like granite, marble, quartz. SAFETY & SECURITY: The Power-supply Cords are attested by UL for security and long-term use. Suitable for voltages from 110V to 130V. EASY TO INSTALL: Can be used by plugging into the socket without tools installed. No extra screws. EXCELLENT COMPATIBILITY: It can work with any brand of garbage disposals(≤2HP), perfectly compatible with Waste King, ISE, Moen, GE and so on. NOTES: The diameter of the countertop hole should be between 1 1/4inch and 1 4/5inch. It is suitable for standard sink hole for soap dispenser.