Zenoah Piston 36mm with Molybdenum Disulfide Friction Reducing Coating - BLACK version - ca332MD-B Zenoah 36mm piston with special factory molybdenum disulfide coating. This is a stock zenoah part # 57479-1001 that has had this special coating added. zenoah part# 584292101 The coating reduces friction slightly, and the reduced resistance results in slightly better performance and top RPMs. These pistons do NOT include a piston ring, requires use of Zenoah pin washers and pin bearings. Professionally coated at the Zenoah factory in Japan. These pistons are a special promotion from Zenoah and may be available only for a limited time! Fits with any Zenoah or CY 36mm cylinder. This is the version of the piston with BLACK coating, as pictured.