This commercial kitchen sink strainer assembly by Gridmann is constructed from rust-proof, heavy-gauge stainless-steel and is perfect for use in any commercial kitchen, laundry, janitorial, or industrial garage sink. It fits 3-1/2" sink openings (overall flange diameter 4-1/2") and has a drain connection made to fit a standard 1-1/2" tailpiece/trap. A post on bottom of strainer allows it to be raised for draining water, or dropped for a tight seal.