The pop-up drain plug mounting nut is made of brass and the end piece is made of 304 stainless steel with a durable brushed nickel finish that resists corrosion and loss of luster. It fits Standard 1-3/4 in. Drain Opening and can also fits drains holes diameter varying from 1-1/2 in. to 1 7/8 in. (1.55 in. to 1.87 in.) It comes in a range of color options to match your bathroom faucet and create a beautifully coordinated look, use it to touch for your bathroom sink.