ESTES 1601 B4-2 Single Stage Model Rocket Engine 3 Pack (Ships USPS Ground Only) HOn3 Couplers Perfect for long hours of

Perfect for long hours of fatigue-free bashing

compressor

And in some

54 cm) Riser pieces - 24 in l x 2 1/2 in w (60

ESTES 1601 B4-2 Single Stage Model Rocket Engine 3 Pack (Ships USPS Ground Only) HOn3 Couplers Perfect for long hours ofESTES 1601 B4 2 Single Stage Model Rocket Engine 3 Pack Ships USPS Ground Only The Estes B4 2 engine is single stage engine designed for model rocket flight. This engine is a standard engine designed for flights in rockets weighing less than 4 ounces, including the engine. Each package includes 3 engines, 4 starters and 4 plugs. SPECIFICATIONS: Length: 2. 8 in. (7 cm) Diameter: 18 mm Estimated Weight: . 66 oz. (18. 7 g) Total Impulse: 5. 00 N sec Time