The GPM SLA155416TLG kit is specified for the 68086-21 TRAXXAS SLASH 4X4 and combines a CNC-friendly aluminium adapter with hardened steel gearing to reduce backlash and improve repeatable power transfer. The matched 54T spur and 16T motor gear maintain robust engagement under load, while the aluminium adapter provides a more rigid mounting point compared to stock plastic parts. Select the gear ratio that matches your motor and terrain for competitive performance and reduced wear.