Item number: LKLY4Take your K'NEX builds to the next level with the RotoKontrol 10-in-1 Motorized Building Set. Use the included K'NEX parts and pieces to build 10 different models like a pirate ship, robot, multiple different wheeled vehicles, and even a Quad-Copter that actually FLYS! The high-speed, precise multi-rotor hub has Beginner and Expert modes to challenge each builder as they enhance their RC skills. And, because crash landings happen, like all K'NEX products, you can easily build and rebuild and get back to the fun in no time! Recommended for builders and flyers age 8 and older. Step-by-step, color-coded instructions are included. Lithium ion battery is required and is included. 3 AA batteries are required, but not included. Most models can be built one at a time.