Designed with an extra-heavy O-ring for a watertight fit, these pry-out plates have nonskid surfaces for horizontal installations. Diamond pattern deck plates have a nonskid surface that extends across the center, eliminating the edge ring that traps dirt and debris. Pry-out plates should not be installed where internal pressure (oil canning) is present. 8 3/8" cutout diameter; 10 1/8" flange diameter.