Perfect Compatibility: The ball bearing of the hose can be rotated and replaced, which is perfect for Polaris 180, 280, 380, 480, 3900 pool cleaner, Replacement Part Number: D20, D-20 (Note: for Polaris 360 POOL CLEANER is not suitable. Quality Improvement: The pool cleaner hose is made of high quality materials and has been rigorously tested by the manufacturer to prevent damage. To connect 2 supply pipes together, 2 pipe nuts and 1 pipe swivel joint are required. Troubleshooting: 1) Rotating wear. 2) Part of the connection is leaking. 3) The pipe becomes stiff and cannot rotate freely. Installation Tips: The arrow always points in the direction of water flow. Water flows from the wall fittings through the hoses to the Polaris pool cleaner. The end of the hose can be softened by immersing the end of the hose in a container (pot or large insulated coffee mug) of hot water so that it can be easily pushed into the unit. Easy Installation: The pool cleaner hose is easy to install and