Slim is in. New SmartlockPro Slim GFCIs Install Easily Industry-leading quality, professional grade lockout action, and the slimmest profile on the market make SmartlockPro Slim GFCIs the smartest choice in ground fault circuit interrupter protection. Faster and easier to install in any wallbox because depth is reduced, theslim GFCIs flush mount to the wall with minimal protrusion for a sleek, finished look. Enhanced features include external back wiring for positive indication the wire is properly seated, exceptional resistance to wire pullout and the ability to withstand hightorque.