POP UP PISTON KITS FITS HUSQVARNA 545, 550 CHAINSAWS 43MM, INCLUDES EVERYTHING IN THE PICTURE, REPLACES HUSQVARNA PART # 57747002, 577047006 THIS KIT WILL FIT THE 550XP, 550, 545 POP UP PISTON WILL INCREASE COMPRESSION AND POWER BE SURE TO MIC YOUR PISTON ASSEMBLY TO ENSURE CORRECT MM SIZE BEFORE ORDERING.
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