Standard thin-wall boxes crack under the repeated torque of outlet and switch installs, replacements, and the seasonal stress of temperature swings in garages and exterior walls - once a box cracks, you're opening the wall to fix it. 3/4-inch knockouts accommodate larger conduit runs for 20-amp circuits, water heater circuits, and dryer or range circuits - the sizes that residential electricians run most in garages and workshops. FSE designation adds the face-seal gasket to the FS design - the integral seal around the device opening that prevents air leakage through the box in exterior wall and conditioned basement applications. 1-3/4-inch depth provides the internal wiring space required for the device and its wire connections. Pre-attached nail tabs for single-drive installation without Stocked at Crofton Lumber and Akron Lumber.