The Coetaneo is a single-layer low profile vessel constructed of clear grey high tempered glass. Novatto uses advanced technology to produce beautiful glass vessel sinks with unmatched structural integrity and longevity. Internal testing has found their high tempered glass to be very durable and forgiving. Made with the highest standards of quality and creative design, Novatto sinks add art and function to any bath or powder room. The Coetaneo vessel has a standard 1.75-inch drain opening. The set includes an oil rubbed bronze pop-up drain and matching mounting ring. For best cleaning results, apply the included Glacier Ice as recommended. Novatto's Glacier Ice wipe-on treatment is a hydrophobic sealer used on glass, ceramics and faucets. Glacier Ice prevents corrosion, oxidation and dirty mineral buildup caused by hard water! Apply just once a year to keep your sink or faucet looking like new. Novatto's customer service is always here to answer any additional technical product questions or help you choose a matching faucet.