Check the listing for details. 3Pack Drain Bladder Unclogs Main Sewer Line For Bathroom Sink Swimming Pool. Condition: New, Made in China. Listed at 28.70 USD. 1.Drain rubber bladder fits 1 to 6 inch drain pipes and inflation pressure between 40 and 80 psi 2.Easy to use: Just hook the drain bladder to a garden hose and feed it at least 6 inches into the drain. Slowly turn on the cold water until the rubber bladder drain cleaner expands to fit closely the pipe wall and then begins to clean. 3.Working principle: Unclog sink drain bladder is designed to expand inside a pipe, seal the pipe, and provide just enough flow to pressurize the pipe behind the clog. Great for unclogging stubborn blockages in outside main drains/sewer lines/bathroom/bathtub/shower/kitchen/basement/swimming pool. 4.The drain bladder unclogger is able to cleanup and rise all soil,mud,silt or other blockages along the flow of the drain to keep the.