The ABB AF31SD is a front hinge designed for 20-inch boxes, commonly used in surface-mounted ReliaGear lighting panel setups. This front-hinged box offers a practical alternative to the door-in-door style, allowing easy access to internal gutters with a simpler and more budget-friendly design. To open the outer door, a contractor needs to remove just four screws, making maintenance straightforward. Distributed by BSP Automation, the AF31SD is a solid choice for those looking to keep their panel access hassle-free without breaking the bank.