Designed especially for use in the installation of signal system and alarm wiring. Base has 1/2" trade size KOs. Larger gang boxes available by special order. Two-gang: 4 3/4" L x 4 3/4" W (121mm x 121mm). Accepts NEMA double-gang standard faceplates. 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. White