For use with 10 (254mm) diameter hole. All devices are recessed 4 1/2 (114mm) below the finished floor level. Unit ships complete with an all aluminum cover (assembled) designed to sit on top of finished floor surface (carpet, tile, wood, concrete or terrazzo). Covers are available in the following powder coated finishes: black (BK), gray (GY), nickel (NK), brass (BS) and aluminum (AL). The covers are also available in two 10ATCPB plated finishes: brass (PB) and satin chrome (SC). Nickel