Normal 0 false false false MicrosoftInternetExplorer4 Product DescriptionThis listing is about a brand new after-market top-quality Piston Ring Set madeby the well-known OEM firm CABERand fits the following PARTNERmodels:500K 500K 500 Mark II510510 CCS550The set consists of one (1) piston ring and replaces PARTNER part #503 28 90-10.Notes:PARTNER part #503 28 90-10 replaced part #505 26 60-65.PARTNER 500 model is different in bore size from Formula 500 model. Piston Rings for Formula 500 model are offered by a separate listing in our eCRATER Store.Shipping Time"Fast Delivery" applies for all our eCRATER items. Our Customer comments about shipping time are more than enough!Just check our eCRATER Feedback pages! Important Notice: If the Part Number of the spare part shown in this eCRATER listing does not match yours, please let us know. Manufacturers often replace old Part Numbers with new ones, as they launch new products in the market. If you don't know the OEM Part Number for the piston rings of your machine, please let us know the dimensions of the piston rings you are looking for (diameter x thickness).