They are definitely handy if you get a fire inside the cockpit. It makes it easier to drive with the visor closed, but I wouldn't rely on it to keep the visor from fogging. I would either get an anti-fog visor from your helmet mfg or I have always buffed dawn dish soap on the inside before a run.
arrace.com seems to be down at the moment. I've used their air system in several cars. Carbon bottle, valve, regulator, hose, and billet clamps. Quality deal. Also have fill hose and scuba big tanks to refill yourself.
Joe is a busy guy, try 619-889-6303 and leave a message.
Or I can find out.
Meyer Race Cars / San Diego
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