Square framed Catch Cover fish house holes are most often used to retrofit fish houses with homemade hole covers already in the floor. The rough floor cut-out is 12-3/4" x 12-3/4". The flange is 1 7/8" tall. Like the Original Round Catch Covers, the Square Catch Covers are injection molded from the proper blend of cold weather materials making them practically indestructible on the ice. The lid snaps into place and won't pop out over the roughest roads, keeping snow and road salt out of your house and all your gear inside the shack! Installation is quick and simple. If you have an existing cutout simply resize the cutout using a skill saw, jig saw, or reciprocating saw. The flange fits flush with your existing floor creating an obstruction free fishing hole. The sleeve system drops right into the integrated lip of the hole opening for a perfect set up. Works best with tapered head stainless steel screws, but drywall screws are fine. Catch Cover features a limited lifetime guarantee, break it and we replace it, no ice shack is complete without the best fish house system on the planet.