For flush sink installation. Tight seal prevents build-up and counter top decomposition. Black sinks are molded in one-piece with rounded corners for easy cleaning. Has sturdy 1-1/4″ flange, tapered sides and 1/4″ wall thickness. Easily installed either flush or below bench level. Integral waste fitting with 1-1/2″ male straight thread (11-1/2 threads per inch). Strainer and plug included. Made of virgin polyolefin resins specially selected to meet the needs of today’s harsh laboratory environments. All have a corner drain fitting.