PLEASE NOTE: This item will ship by US Postal Service Parcel Post only. You MUST HAVE a physical mailbox or post office box for delivery.
The Estes B4-4 engine is single stage engine designed for model rocket flight. This engine is a standard engine designed for flights in rockets weighing less than 3.5 ounces, including the engine. Each package includes 3 engines, 4 starters and 4 plugs.