TŁOK KOMPLETNY HUSQVARNA 254 AIP Piston diameter 45mm Piston height 39mm Ring thickness 1.5 mm (1 piece) Piston pin 12mm x 30mm Original number (comparison no.): 503 50 37-01 Reference No. This is not an original spare part, but a high quality (OEM) replica part in OEM quality. Original part number and brand names are for comparison purposes only.