This is an Supply Giant nipple fitting with male threaded ends, which is made of steel with a black coating for improved durability of the Part. This close nipple is 2-1/2" long, with virtually no pipe between the two threaded ends. The nominal pipe size diameter is 2-1/2" and it has a wall thickness which is specified as Schedule 40. The fitting meets all applicable ansi and ASTM standards. ⚠ California Proposition 65 Warning: This product is known to the state of California to cause cancer, or other reproductive harm. For more information, go to www.p65warnings.ca.gov.