High Craftsmanship: The whole V2 engine is made of metal. With CNC precision casting process, aluminum alloy oxidation, looks gorgeous. The mechanical mechanism is extremely presented, and the clear transmission process is clear at a glance, and the mechanical beauty of the logic and strength is displayed. Ideal for gift collection. Fun Assembly Kit: The V2 engine is consisting of 217 pcs, the whole assembly process take around 3 hours. While assembly, you will understand the V2 engine working structure. Challenge yourself and prove yourself, build confident in between. Working Principle: It is an electric engine, works with electric motor and 450mAh lithium battery. Ideal Gift Choice: With competitive price and high-end package, ideal gift for yourself, friends, kids, colleagues or family members. They will 100% love it. Material: Aluminum Alloy + Stainless Steel. Charging voltage: DC 5V. Lithium Battery Capacity: 3.7V, 450mAh. Charging time: 2 hours. Working time: 1.5 hours. Assembly time: about 3 hours. Assembly difficulty: IV grade. Metal Box Size: 342242150mm. Suitable age: above 14 years’ old. 1 Set x V2 Engine Assembly Kit (217pcs). 1 Set x User Manual. 1 Set x Tool.