Search query: b4-4 rocket engines

Product: The Original Stomp Rocket Ultra Rocket Launcher, 4 Rockets and Toy Air Rocket Launcher - Outdoor Rocket STEM Gift for Boys and Girls Ages 5 Years and Up - Great for Outdoor Play
Brand: Stomp Rocket
Color: Red
Relevance: Irrelevant
100% KID powered: Run, jump and STOMP to launch these rockets up to 20 stories high -- that’s 200 feet in the air! No batteries required; easy, fast assembly.
Award-winning products from industry experts, including iParenting Media, Dr. Toy, and Creative Child Magazine.
Includes a Stomp Launcher, 4 foam-tipped Ultra Stomp Rockets that work with three different Stomp Rocket Launch Sets.
Pair with Stomp Rocket Science book and get kids interested in STEM subjects (Science, Technology, Engineering, and Math) early. Ages 5 and up.
Great for year round fun to get kids away from screen time and more active outside.

Product: Estes C6-3 Engine Pack (3-Each)
Brand: Estes
Color: C6-3 3/Each
Relevance: Substitute
Includes 3 - C6-3 Engines, 3 - Starters, 4 - Starter Plugs
This engine is a standard engine designed for flights in rockets weighing less than 4 ounces, including the engine
Single stage engine

Product: Estes Mini Rocket Engine 1/2A3-4T
Brand: Estes
Relevance: Exact
Includes 4 - 1/2 A3-4T Engines, 4 - Starters, 4 - Starter Plugs
Mini engine designed for lightweight rockets
Single stage engine

Product: Estes 2274 Recovery Wadding
Brand: Estes
Color: Multi
Relevance: Irrelevant
There’s no thrill quite like launching a model rocket, watching it streak skyward, reach peak altitude, and then return gently to earth. When you build them, the thrill is even better than ever. Thanks to Estes model rocketry, kids can explore the wondrous world of science while experimenting with different combinations of rockets, engines and accessories to better understand how rockets reach outer space.
Flame resistant recovery wadding protects the recovery system.
Necessary to launch model rockets.

Product: Estes C6-7 Engine Pack (3-Each)
Brand: Estes
Relevance: Substitute
Includes 3 - C6-7 Engines, 3 - Starters, 4 - Starter Plugs
This engine can also be used as a single stage engine in lightweight rockets
Upper stage engine

Product: Tandem-X Launch Set (Amazon and Crossfire ISX)
Brand: Estes
Color: Orange
Relevance: Irrelevant
The is quick and easy to assemble, This huge rocket, standing 30in tall, can reach heights over 650 feet with recovery on a colorful 18 inch preassembled parachute
The Crossfire can easily be built in about a day and features a totally streamlined shape with aerodynamic fins and nose cone. This bullet can reach Cloud busting heights up to 1, 200 feet
Estes model rocketry is recommended for ages 10 and up with adult supervision for those under 12. Recommended engines: a8-3 (first Flight), b4-4, b6-4, c6-5, c6-7
Tools, construction and finishing supplies sold separately. In order to launch, model rocket engines, starters and recovery wadding are required - sold separately