Estes, Booster 60 Almost Ready To Fly Kit, A Must Have Accessory To Fly Those Rockets Even Higher, Add Up To 800' To Your Flight, Designed Specifically For Use With The 2486 Flying Colors, 2487 Helios & 2488 Firestorm Model Rockets, Booster Uses 1 D12-0 Model Rocket Booster Engine, Sold Separately, Minor Assembly Is Required.