Over-revving your Menace HP tires could result in breaking the internal belt

or bend like the stock unit

Genuine Losi part TLR244044

Multiple openings for different shock sizes

Traxxas 9891 TRX-4M High/Low 2-Speed Transmission HO Figuers Over-revving your Menace HP tiresTraxxas 9891 TRX 4M High Low 2 Speed Transmission A New Level of Crawling Capability Add enhanced crawling capability to your TRX 4M with the new High Low 2 speed transmission. The manually selectable unit adds a low gear option for incredible rock crawling torque, while keeping the standard high gear ratio for general driving. The transmission comes fully assembled and ready to install with a new Titan 180 motor and mounting bracket. Note: The High