The Classy Caps PVC adapter is available in a white or tan finish and was made to fit over a 3.5 in. x 3.5 in. post. This 3.5" x 3.5" adapter is compatible with Classy Caps model #SL078T/SLO78W Regal Solar Post Cap as well as model #SL074T/SLO74W Classy Solar Post Cap.