They're free hub carrier components for the TRF420 racing car framework. They have been a better and more durable design compared to the past design found in the TRF417/418/419 era of automobiles.
• TRF420 F Parts x1
• Components are molded in carbon fiber-reinforced plastic for superior rigidity.
• the look ended up being revised specifically for the TRF420 framework, with greater opposition to shocks and crashes.
• Upper and reduced flanged pipes are now actually identical.
• to be used with 3mm diameter shafts (offered in Item 51637).
• appropriate for vehicles using Item 51639 TRF420 D Parts (suspension system hands).