In my words
I bolt Upgrade C Hinge Pin Holder PRO-MT 4x4 on before a race weekend, not after one.
Spares exist so a broken part costs you a heat race instead of a weekend.
Stock on small-batch sets moves quickly, so the listing is the honest source for what is left.
What Pro-Line says about it
- Made from 7075 Black Anodized Aluminum
- Nearly Twice as Thick as Stock Holders
- Intended for Extreme Durability
- Maintains Same Exact Geometry as Stock
Questions I get about this set
Aluminum or plastic?
Aluminum holds geometry and transfers the hit; plastic bends and comes back. On a rough outdoor track I take plastic in the front and aluminum in the back.
Do I need special tools?
A hex driver set that actually fits, thread-lock and a bench. Rounded hardware costs more time than any part on this page.
