PISTON (0.50 - OVERSIZE - DIAMETER: 108.45 mm - WITH ALFIN) : LISTER / HR-4 / HRA-4 / HRW-4 / HR-6 / ;HRA-6 / HRW-6 / PISTONS INCLUDES PISTON PIN AND SAFETY RINGS / (The reference numbers given on the products are for checking the products.)