Estes-Cox B6-4 Rocket Engine -
A standard, single-stage model rocket engine for flights in rockets that weigh less than 4 oz. with engine in place. Each package contains three Estes B6-4 rocket engines, three igniters and four igniter plugs. Rocket, launch system and recovery wadding not included. Model rocketry is recommended for ages 10 and up with adult supervision.
Attention residents of California, New Jersey, Rhode Island and North Dakota, the following age restrictions apply to the purchase of model rocket engines. In California, one must be at least 14 years old to purchase engines through size D and 18 to purchase larger than D. In New Jersey, one must be 14 to purchase engines through size C and 18 to purchase larger than C. In Rhode Island, one must be 16 to purchase engines through size F. In North Dakota, one must be at least 10 to purchase engines through size D and 14 to purchase larger than D.