Part 71903 Center Stand Pipe for 19" Sand Filter TanksReplacement internal standpipe for Swimline Hydrotools 19" sand filters and sand filter systems systems The Part 71903 Center Stand Pipe for 19 Inch Sand Filter System Tanks Features Include Genuine Hydrotools replacement part for Hydrotools 19" sand filters and sand filter systems Replaces standpipe found in Model 71915 sand filter systems Replacement standpipe for Model 71900 sand filter Constructed of heavy duty materials Genuine Hydrotools