These cone springs will require Hilo adjustable suspension as they sit higher than the originals.Containg an anti fade property and shape which helps them going off during racing and giving hopefully a season of racing before replacement. A softer road going compound is
C-STR687. The thick top plate has an internal thread rather than the nut welded in place as per the standard cone springs or copies. these have a yellow dot on the metal base for identification purposes.
These are manufactured by a highly technical company involed in rubber on Formula 1 cars.
If using these on 10" wheels with Hilos cut 3/4" off the end of the centre threaded bolt of the old type Hilo with a circlip as it will bottom out on the cone spring face and the car will sit high, for extremely lowered cars the hilo face will also need machining a few mm.
Like all rubber products -they only have a certain shelf life and being fitted equates to the same.Sold singly and advise fitting in axle pairs.