Bomar Commercial Grade Aluminum Inspection Hatch 8-13/16 inch x 11-1/8 inch Rectangle 2-Dog Low Profile. Hatch is made of Almag-35 Aluminum and has removable lid for easy access. Locks down with two t-handles. Non-skid surface. Hatch Opening: 8-13/16 inches x 11-1/8 inches (224 x 328 millimeters), Outside Deck Flange: 13-1/16 inches x 15-5/16 inches (335 x 389 millimeters), Cutout: 10-3/4 inches x 12-7/8 inches (273 x 327 millimeters), Extends below deck: 1/2 inch (13 millimeters), Weight: 7 pounds.