The B6-4 is a widely trusted and well-balanced engine that offers reliable performance across a variety of model rocket kits. With a moderate level of thrust and a 4-second delay, it allows rockets to coast effectively before activating the recovery system, making it ideal for rockets that benefit from a longer delay phase after burnout.

Designed for single-stage rockets weighing less than 4.0 ounces, the B6-4 engine delivers consistent results and controlled recoveries, making it a great fit for both new flyers refining their skills and seasoned hobbyists looking for dependable flight profiles.

Whether you're launching for fun or using rockets in a STEM learning environment, the B6-4 engine provides an excellent combination of power, altitude, and control. Its predictable performance has made it a go-to for generations of rocketeers.

Each 3-pack includes everything you need for multiple flights: three B6-4 engines, starters, plugs, and recovery wadding. Just pair with your favorite Estes rocket and launch system for a fun and educational experience.

ATTENTION: Estes Industries, LLC requires all purchasers and users of Estes® Model Rocket Engines to adhere strictly to all applicable local, state, and federal laws, regulations, and safety standards. The user assumes all responsibility for the safe and lawful use of Estes® products. Estes Industries, LLC expressly disclaims any and all liability for personal injury, property damage, or other loss resulting from the misuse, improper handling, or unauthorized application of its model rocket engines.