The Fox Twin Clicker:

Fox Racing Shox has ceased production of parts for the Twin Clicker for race cars.  While they now prefer to limit their efforts to various forms of off-road and bikes, Shock Shop is a Fox dealer and still has some parts for the Twin Clicker.  Routine service, repair, revalving and Critical Damping Analysis are all available from Shock Shop for these shocks as long as parts are available. 

The Fox Racing Shox Twin Clicker was a significant advancement in its day.  It can still be a reasonably good damper for club and vintage racing.  However, it can not perform as well as modern day products.

One might consider upgrading to a modern set of dampers for maximum performance racing, then set up the Fox's with appropriate springs for a quick change to yield significantly improved performance in wet conditions.