This TBAO piston kit is a great choice for Yamaha1999-2023 YZ250 and YZ250X models, as well as Suzuki RM250 models from 2003-2008. The kit is made from high-quality aluminum alloy and comes with a 3-month manufacturer warranty. The cylinder bore diameter is 66.4 and the kit includes all the necessary components for a successful installation. The kit is packaged in its original box, although the packaging may differ from what is found in a retail store. See the seller's listing for full details. This piston kit is perfect for anyone looking to upgrade their motorcycle's performance.                 High silicon eutectic + Cerakote molybdenum disulfide coating + Top Cerakote thermal insulation coating +RIK piston ring = High pressure, wear, corrosion and durability