An additional piece of aluminum, surrounding the inspection port opening, is welded to the inside of the tank. This creates a flange, .4" thick and 1" wide. The flange both stiffens the tank and provides more aluminum for the threads of the closing fasteners to engage.

• Diameter: 6"
• Opening: 4"
• Tank flange thickness: .4"

1) Some of the aluminum tanks we offer include an interior baffle to prevent the fuel from sloshing around in the tank while underway. As a result, one or two inspection ports may be added in order to gain complete access to clean the interior of the tank.

2) A 50% nonrefundable deposit will be billed when your order for this item is accepted. The balance will be billed when the product ships.

3) This is a custom optional upgrade for the fuel tank you have ordered. Once you order this option, it is going to be added to the fuel tank just for you, just as you asked. We never want to see it again, and no else wants it either. So be careful and order it correctly the first time because it can't be canceled, returned, or magically changed into something different!