Focus Mk2 RS/ST Mahle Motorsport Forged Piston SetFocus Mk2 RS ST Mahle Motorsport Forged Piston Set SImply The Best Focus RS ST Pistons Available MAHLE Motorsport Piston Set Ford Focus RS ST MK2 2. 5 Forged Pistons set manufactured by MAHLE Motorsport. For Focus ST use, rods should be changed to RS items. Dual coated pistons dry phospate coated to prevent microwelding and piston pin galling give these MAHLE pistons their signature grey appearance. Graphal skirt coaring to reduce friction. Supplied