Mansfield Waverly Drop-in with a 4" center Model 257-4-BISC is a Biscuit 21?x17?rectangular sink. This lavatory if you so choose can be used with a wall mounted faucet. The Mansfield Waverly Drop-In Lavatory with a 4" center Model 257-4-BISC is made of a durable vitreous china material with a front overflow. The Mansfield Waverly Drop-in Lavatory with a 4" center Model 257-4-BISC comes with the limited lifetime Mansfield warranty. Mansfield is an American company that?s been in business since 1929, and has been one of the top producers in design, and quality for the past 40 years. They are the largest domestic producer of sanitary ware, and strive to ensure you get the best products available.