I have a T1. Ran the car for the last year, Like the last post, upper transponder mount/bumper support, impact front bumper and C hub front arms and rear arm is all I have broke. Get the upper support, impact bumper, front lower arm, rear lower arm and the extra screw kit. Always nice to have a few extra screws around for when you drop one in a race. I race carpet with the C Hub. Asphalt I would use pillow ball. Extra $20 for both?? I would!! I paid dearly for the C-Hub option.