The 25-inch wheel aluminum alloy frame mountain bike cycling bicycle black is with multi-color led light, can flight in the dark at night. the features of the bicycle have 3 types of riding: Booster riding, pure electric riding, and pure human riding. It is a 21-speed transmission gear shift system! the front fork is high-strength carbon steel comfort shock absorption! the electric bike is a bike that will get you where you need to go and allow you to have a little fun along the way. Ultra-lightweight material-the e-bike adopts a 100% aluminum alloy frame, the front fork is made of high-strength carbon steel and packed with premium comfort shock absorption. the aluminum alloy frame light, strong and designed to last, makes it easy to maneuver. aluminum alloy double-walled rims are for greater durability as well as faster ride with less drag. Equipped with a powerful 500w motor: The mountain bike is equipped with a 500w high-speed brushless motor, providing more than enough to power your daily commute, a cruise on the mountain, or a meander along your favorite trail. With speeds up to 20 mph, it will get you there swiftly. 12. 5 ah removable lithium battery & new-quick charge technology-Equipped with large capacity 12. 5 ah removable lithium battery, you can reach a range of up to 35-40 miles at a topped speed of 20mph per charge. Plea by for a day adventure or most trips to travel and back. you can charge the battery on/off the bike at your convenience. equipped with a smart lithium battery charger. Easy charge system needs only 4-6 hours. Brake & gear shift system-with front and rear disc brakes and 21-speed transmission system, perfect brakes fully protect your safety. 21-speed gear increases hill-climbing power, further range variation, and greater terrain adaptability. Ergonomic design-Ergonomic handlebar, adjustable seat and rest, anti-slip, and wear-resistant. And the led handlebar display design lets you can check the battery life, turn on the headlight, honk the horn, accelerate, brake all from the handlebars. the lightweight and efficient design help to travel further and save energy. 3 working modes for your choice: E-bike & Assisted bicycle & normal bicycle, you can choose the e-bike to enjoy long time travel, and also exercise. Combining two modes would be a better choice. Specification: Brand: Generic Frame material: aluminum handlebars: aluminum alloy color: Black Meter: Led 3-speed smart meter button Dimension: 21 inch number of speeds: 21 speed full length: 160 cm/ 63 inch heel diameter: 63 cm/ 24. 8 inches size: 26 x 17 cm/ 10. 2 x7 inch handlebars length: 60cm/ 23. 6 inch lithium battery size:5 x 8 x 35 cm/1 x3 x 13. 8 inch basic information: Net weight: about 23kg/50lbsBattery weight: about7kgBattery capacity: 36v 12. 5ahMileage: 35-40 miles Lithium battery: 36vCharger: Smart lithium battery charger charging time: 4-6 hours motor: 36v 500w high-speed brushless gear motors. Load capacity: 150kgMaximum speed: 20mphPackage content: 1 x electric bike (with accessory).