The Danco 1.75 in. O.D. Kitchen Air Gap Cap in Brushed Nickel 10567 is a single unit kitchen accessory designed to prevent air from entering the sink while still allowing water to flow freely. Made by the trusted brand Danco, this brushed nickel cap is a stylish and functional addition to any kitchen. Perfect for home improvement projects related to plumbing and fixtures, this air gap cap ensures a clean and efficient sink experience.