The PolylokHeavy Duty Grate lid fits inside diameter single wall and double wall corrugated pipe. This cover is perfect for high foot traffic installations! This lid is flat and includes a skid resistant surface. Every cover comes with a factory-installed gasket to ensure an airtight and watertight seal!

Poly lock plastic cover.  (this comes in two sizes:  18 and 24).  We do offer steel bolted covers and concrete covers as special order items