Tractive Rear Shock X-TREME + HPA for HUSQVARNA Norden 901 (2022-)This shock absorber uses a damping shim stack specifically developed for its application. The aluminum shock absorber housing creates maximum thermal stability by optimal heat removal. Not only leads this to stable performance but also to a longer lifetime of the shock and its oil. To create the best performance for every model we use high flow pistons, low friction seals, and dedicated shimstacks. We use heavy duty components like microfinished