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Estes: Primary supplier for A-E motors. These can also be found in some hobby stores. Avoid the larger (E and above) motors, as they have a very high failure rate.
Quest: Similar to Estes, but with a smaller market share.
High Power:
Cesaroni Technologies, Inc.: Our main supplier for rocket motors. AMW/ProX sells their stuff and is usually on-site for MA/ME-based launches. They very polite, occasionally difficult to reach. Factory explosion occurred Spring 2016, supply will be limited for 8+ months.
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