The last and only C6-6 that existed was the Cox 18mm C6-6 that ended in 1972.
None existed in 24mm. If 24mm, it would have to be an Estes 24mm C11-5.

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !