With their additional cubic capacity, this family of boxes is designed for any installations that require a greater number of conductors such as heating, GFCI and arc-fault applications. What's more, because it's an LHTQ, installation is always fast and accurate. Look for these practical and time saving features on all LHTQ models. Gangable device box 3 inches height x 2 inches width x 2-1/2 inches depth 14.5 cubic inches volume. Positioning tabs. One screw mounting.