Aluminum Alloy Rear Derailleur Sturmey-Archer Internal 3-speed Power System Motor 250W 24V DC Brushless Hub Motor Battery 24V 6Ah Lithium Battery Display LCD Backlight Display Sensor Intelligent Pedal Torque Sensor The db0 folding electric bike is the newest bike by DK City and ROBRADY. The name stands for "Divided By Zero." It's got a sleek look and a powerful kick, with a pedal-assist to help you ride Wheel Size 20" Rim 20"x13Gx36H Alu-Alloy Tire 20" x 1.95 Frame up those tough hills. For the coolest electric bike that will stand out in the crowd, the db0 is the best ride around. The db0 folding electric bike is the best of both worlds. It's a folding bike with a compact shape, so it fits into smaller places like closets and car trunks. It's also a Lithium-based electric bike, with a 250 Watt motor providing assistance as the rider pedals the bike. Did we mention it looks sweet? db0 folding electric bike features: 3 Modes of torque-sensitive pedal-assist Internal 3-speed internal hub gears to climb steep hills Simple 10-second folding process Just look at that sweet design! The db0 folding electric bike is able to have such folding size because both the front fork and the rear chain stay are just single arms. This allows the 20" wheels to fold closer together, for a more compact shape. When completely folded, this bike can be carried by a handle on the frame. It's super convenient to transport. Riding the db0 folding electric bike is like riding a regular bike with an assisted boost. When pressure is applied to the pedals, one of three modes of assistance kicks in. This helps to power the rider up hills, through a long commute, or to help out riders who don't have as much leg strength. The db0 folding electric bike is a great option to bring on a boat, on a vacation to the beach, or to ride around the city. It also has enough battery life to go 20 miles on a single charge. You won't have to worry about getting tired on a long bike trip anymore!