B&B 541-3-A Black Deluxe Round Electric Cable Hatch with Back
—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″.