Diameter: approx. 2.79 cm. Inside diameter: approx. 1.52 cm. Quantity: set of 4 Ball bearing piece C60 (C-60): This ball bearing for pool cleaner is perfectly compatible with 180 and 280 pressure washer wheels. Spare parts: This ball bearing C60 is suitable for the pool cleaner Zodiac Polaris 180, 280 swimming pool. Quality Assurance: Replacement parts are made from high quality, durable materials and have been thoroughly tested by the manufacturer. Save time : this spare part is of high quality and easy to install, so you can save money and time. Scope of delivery: the package includes 4 or 8 pieces of bearings of wheel for Polaris 280 180 pool cleaner. Features: Name: ball bearing for pool cleaner. Material: plastic. Compatibility: (for re ference only). Alternative to Polaris part number: C60 C-60. Fits Polaris 180 and 280 models. Contents: 4 pool cleaner ball bearings or 8 pool cleaner ball bearings. Notes: Due to lighting effects and angles shooting, the item's color may be slightly different from the picture. Due to manual measurement, there may be some error in the size of the product. .