For Deep Devices Such As Momentary Contact, Remote Control Switches, and Hospital Signaling System Devices. Base Has 1/2" Trade Size Kos. Larger Gang Boxes Available By Special Order. Three-Gang: 4 5/8" L X 6 1/2" W (117MM X 165MM). Note: Certified to Canadian Safety Standards For Sale In Canada. When Ordering These Products, Change The "V" Color Prefix to "VC" or The "WH" Color Suffix to "WHC" to Denote The Canadian Versions.