This is the RDLogics Purple Aluminum Heavy-Duty Suspension Arm Set for the HPI Savage trucks.  This will fit the Savage X, XL, 21, 25, and Savage SS trucks.  This includes four heavy-duty lower suspension arms and four heavy-duty adjustable upper suspension arms.  The adjustable arms make it possible to tune your truck to the track or driving condtions better, making your truck handle better.  This is one of the most durable sets of suspension arms we have found for the Savage trucks.  They look great on show trucks too!