Review on SEAFLO Black Circular Non Slip Inspection Hatch with Detachable Cover - 4-8 inches: Slip-Proof & Convenient Access Solution by Javein Harvey

This hatch provided ample space to access the interior of my small boat for wiring projects. I used the inside diameter of the manhole to mark the access hole and then enlarged it by 1/5th. The result is a perfect fit. The lid closes tightly and I've made it waterproof by applying some silicone to the outer ring and stainless steel screws. I need to make some 4 inch hatches to access the rear battery compartment. Good thing.