MODEL NUMBER: G52 Back Up Valve Kit, including G53 Gear Mechanism, G54 Outer Casing and G57 Outer Ring. This item is also suitable in salt water pool EASY TO INSTALL: It is made exactly fit for Zodiac models 180, 380, 280, 480 PRO, 3900 Sport, Vac-Sweep 380, Vac-Sweep 280, 280 TankTrax. Easy to install, you only need to connect the fittings and hoses tightly to work PREMIUM QUALITY: The replacement part features a study and wear- polymer blend and construction reduce cracking on the valve case, well-tested by the manufacturer - Meet Part Number standards - long lasting and effective operation. This part is re-engineered with upgraded wear bushings, axle, and gearing to improve back up valve function and lifespan. Salt water pool is also suitable FUNCTION: If your cleaner is experiencing issues such as stuck on edges of the pool or having a hard time turning around, this could be due to a faulty back-up valve. Our G52 Back Up Valve Kit reduces leaking water out of the side port when the valve is not in backup mode, increasing pressure to the pool cleaner and improving cleaner performance Colour:White Material:plastic Package Contents: 1 x Backup Valve Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.