This is an optional Mugen Seiki Non-Trailing Front Hub Carrier Set, for use with the MBX7 family of buggies, trucks, and GT. Package includes one left and right side, as well as four inserts. These uprights have smoother steering compared to the E2147 trailing front uprights and work great in high traction conditions. E2146 uprights can be used with both CVA and universal style driveshafts.