The Estes F15-4 engine is a mid-power workhorse designed for model rocket launches requiring more thrust and longer burn durations. With 49.61 N-sec of total impulse and 25.26 Newtons of max thrust, this engine is built to lift rockets weighing up to 21 ounces, making it a strong seller for advanced hobbyists and mid-power enthusiasts.
 Retailers and distributors will appreciate the F15-4’s position in the Estes lineup—it fills the gap between standard D/E engines and composite motors. The 3.45-second thrust duration gives rockets a sustained climb, while the 4-second delay ensures smooth deployment at apogee. It's a smart option for customers who want dependable performance without the need for reloadable systems.
 Compatible with a wide range of rockets featuring 29 mm engine mounts, the F15-4 is a go-to choice for launching payloads, larger airframes, or sport rockets in club and hobby settings. It’s particularly well-suited for use with Estes Pro Series II rockets and similar kits.
 Stocking the Estes F15-4 provides your customers with a powerful, black powder option that delivers reliable results and expands their launch capabilities. Each pack includes 2 engines, 2 starters, and 4 starter plugs—ideal for club launches, workshops, or mid-power demos.
 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.