Schelle is offering the pre-assembled T6.1 91mm Aluminum CVA Bones by MOD Speedshop for racers wanting to shed some weight for 17.5 racing on dirt (also fits SC6.1).

The 2 piece bones utilize a lightweight aluminum pin drive shaft mated to proven MIP steel CVA yokes. Pin drive bones work with the kit T6.1 steel outdrives, or B6.1 series pin drive Bi-Metal MIP differentials (see SCH1259 pin drive B6.1 Bi-Metal diff) and have a positive driving feel, locking the rear end in on-power. Many racers like the feel of pin drive shafts because they enable the buggy to set into the corners and carve without getting upset by small steering inputs or bumps. With the MOD Light Bones, racers get the best of both worlds, light weight and stable handling.

Features:

Rotating weight savings. 7.5 grams vs 11 grams for steel kit units.
Rebuildable 2 piece design, change either the aluminum bones* or steel CVA yokes.
Pre-assembled in cooperation with MOD and MIP using genuine parts.
Works for 17.5 motors on dirt. Not recommended for Modified or turf/carpet.
For added security, run an o-ring up-travel limiter on your rear shocks.
Fits T6.1 and SC6.1 direct fit.