The “U Bushing” was created to simply allow a smaller sized pipe to be inserted in a larger UCON Systems connector. For example, some fence builders want to use 2 7/8” posts but then run a 2 3/8” top rail. This bushing will allow the builder to securely insert the 2 3/8” into the 2 7/8” UCON Systems connector. Problem solved! Available in 1 finish and 2 sizes. See the .PDF for more technical specifications.