Surface 604 Element Wide Grip Electric Fat Bike Aluminum Allow 6061 Super-light aluminum-alloy 6061 custom-built frame for easier pedaling. Four-inch tires for riding softer surfaces and terrain. 350-watt (750-watt peak) brushless motor for more-efficient riding. 36-watt/12V removable battery for traveling further and faster. Control panel with three power modes to choose from: low, medium, high. Includes SHIMANO parts and components such as SHIMANO TX50 Shifter, SHIMANO TZ20 Freewheel and a SHIMANO Tourney RD-TXX GS Derailler. Rear rack is completely removeable!