This is the optional Differential Spool for the Traxxas Revo, TRAC71**.
Constructed of steel
Installs in diff housing on either front or rear wheels
One Differential Spool for the Traxxas Revo with instruction sheet
Differential Ring Gear and Pinion, TRA5379
Length: 2.3" (58.4mm)
Use only on off-road low-traction conditions to avoid damage to driveline components