Black plastic. Built-in five pin tumbler lock, supplied with two keys. Gasket to prevent moisture from entering tank, Will fit Perko Gas Fills, 1313, 1413 and 1513 already in use.

 PROP 65 WARNING: This product may contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling. For more information, visit www.P65Warnings.ca.gov