Strongest hinge on the market Vermin door accepts both 30 and 50 Amp cord Replaces any round hatch up to 4-1/2'? Door has a 'snap-lock' feature Cutout Dimension: 3-1/2' diameter; Outside Dimension: 5-1/8'; Collar Depth: 2-3/8' JR Products 541-2-A Deluxe Round Electric Cable Hatch - Polar White SKU: 154.1282 UPC: 756815001045