Finally, a quality shock for your ruckus, or dio. 245mm, fits gy6 ruck, Get ruck, and dio/met. This shock is unlike the ebay/no name special. The majority of shocks come out of taiwan/china, and generally don't ride that great. Cheap construction/materials will always fail sooner. Adjustable preload, and firmness setting. Simply twist the black dial down low, to change. its that simple.