Tamiya Soft T-Bar (#54165)/ 3Racing (#F104-07/15/FG) T-Bar 1.5mm/ 3Racing (#F104-07/18/FG) T-Bar 1.8mm
The T-Bar and the M04 spring offer stability to the car, especially when running over bumps. The soft T-Bar also improves rear grip when running on low friction tracks.
TRG (#TRG5101) Hybrid Motor Mount/ 3Racing (#F104-09/LB) Motor Mount
Meanwhile, the aluminum motor mount maintains cooler motor temperatures; this will offer better protection to the motor, making it long lasting.
Tamiya F104 HT Servo Saver (54159) / 3Racing (#3RAC-SHAMU) Servo Saver
Enhanced the steering and handling, improved precision for turning. It will also protect the servo gears from impacts, making Tamiya F104 tougher.