... Roller or V brake17)Brake level: Shimano, power off18)Speed gears: SHIMANO inner Nexus 819)full chain cover, plastic ... )Stem: alloy,adjustable, dutch style22)Chain: Rust resistant, high speed chain23)Crank: alloy crank24)Mudguard: alloy foil,foldable25)Rear rack ... steel 13# spokes with brass nipple31) LCD display: showing speed,Battery capability, Assistance level, cycling distance&time etc.G./N ...