I have had/flown several Estes & Centuri 18mm "green" paper motors in the past.
I actually have had MORE 13mm Centuri "long" mini-motors in A4-xM and B4-xM varieties in green than any of the 18mm stuff.
Seem to remember flying some "blue" 13mm Centuri Mini-Motors too, but may be wrong on that one.
Unfortunately I have no intact/unfired or fired "long" Centuri mini-motors any longer.

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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 !