I had a 6" hat light in a fiberglass tub/shower. This block was the easiest replacement imaginable. Make sure to turn off the device. After removing the "Can" portion of the old light and removing the 3 wire Romex, the new light received simple color coded plug connections. Ground wire, bare or green, is NOT used on this instrument. Remove the connector on the back of the new light, pull out the quick connector, insert white on white, black on black into the hole next to the new mounting wire. Then simply push the spring-loaded wings up through the opening and you're done. If you need a dimmer, all LED lights need a special dimmer, such as B. the Lutron L. Works great with just one pole switch.