ST Racing Concepts - CNC Aluminum Threaded Shock Bodies w/Collars (1 pr), for Traxxas 4Tec 2.0 (Blue)
These are threaded shock bodies with aluminum lower caps and o-ring installed shock collar. Aluminum shock bodies provides a much smoother shock action by reducing the friction between the shock piston and the inside of the shock bodies, while the threaded shock collars provides a much more precise increments of shock pre-load for the desire suspension feel and ride height.