HPI 72215 Gear Diff Adjustment Spring Set Medium Firm & Stif Tires/Wheels Replace a cracked seat or

Replace a cracked seat or battery box with this set to keep your Promoto-MX complete and running

Smart technology ensures that all of your model's electronics work together seamlessly for the greatest efficiency and performance

This gear is a straightforward way to fine-tune gearing or replace a worn factory spur gear

0 Black #TEC4-S01BK

HPI 72215 Gear Diff Adjustment Spring Set Medium Firm & Stif Tires/Wheels Replace a cracked seat orHPI 72215 Gear Diff Adjustment Spring Set Medium Firm & Stif Genuine HPI Racing gear diff adjustment spring set including medium, firm, and stiff options. Swapping diff springs changes how the differential loads up, letting you tune power delivery and cornering behavior to suit your driving. A simple, effective tuning set that also replaces worn springs to restore consistent diff action. Genuine HPI Racing part #72215 Gear diff adjustment spring set