Tamiya 9803402 Stiffener Nut for TRF420X - Chassis Locking Fastener  [9803402]

How the stiffener nut fits and performs

This Tamiya 9803402 stiffener nut (part no. 42382) functions as a compact locking fastener intended for TRF420/TRF420X hop-up assemblies. It secures stiffener plates and braces so preload and alignment are preserved while you experiment with chassis flex and rigidity. The emphasis is on compatibility and role in tuning rather than specifying measurements.

In real-world use the nut is fitted where the chassis requires a locking or reinforcing point for a plate or brace. When you change plates, add inserts, or alter chassis stiffness, this nut holds the assembly position and reduces unwanted movement that may shift balance. Follow safe workshop practice for tightening, do not over-torque near composite or thin aluminium parts, and inspect threads and seating surfaces if reusing hardware.

For hobbyists concentrating on durability, this component preserves mechanical joins rather than changing suspension geometry or electronics. Keep spares and check for thread wear when swapping hop-ups often.