Square framed Catch Covers 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 inches x 12-3/4 inches. The flange is 1 7/8 inch 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 indestructable 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 house!