DNM Rear Shock Spring 550LBS 150MM For Pit Dirt Bike This rear shock spring is designed for pit dirt bikes and features a 550LBS spring rate with a length of 150mm.It is compatible with DNM suspension systems and provides consistent performance under regular riding conditions.The spring is constructed to maintain durability and shape retention over time.It installs directly into the rear shock assembly and supports stable rear-end handling. This is a compatible aftermarket part.References to brands or models do not imply OEM association.