6KU Aluminum Fixed Gear Single-Speed Fixie Urban Track Bike 6061 double butted alloy smooth welding 32H F/R flip-flop hub for optional fixed or free wheel riding 1 1/8 inch alloy fork. 700 x 25C Kenda Tires and Novatec Flip-Flop hub 30mm deep V double wall alloy wheels with a flip-flop hub Easy removable front/rear brakes