From Custom Works RC:
This new blue aluminum transmission case offers a precision machined fit for the most efficient operation possible. It also moves the motor to the right to center it in the car and give a more even weight across the rear tires for an even straighter launch. Includes a carbon fiber motor mount and a motor brace to help support the motor and prevent any flexing of the mount and gear mesh. These are in stock now and ready to ship and includes case, hardware, motor mount and brace. You will need the internal parts from the stock transmission as well as the R1wurks V2 Top Shaft and slipper eliminator.
NOTE: These will not work in our oval cars with the included motor mount. More info on an oval car version will be coming soon.