Higher performance 27 x 1 flip flop hub wheel set for your FIXIE conversion. Flip flop Formula Sealed FX hub with stepped thread accepts a 16T freewheel on one side and a 16T fixed gear cog or higher on the other side. Strong alloy bolt-on front and rear wheels are hand-built in the USA by Wheel Master with 36-Hole Sun CR18 rims, and stainless steel DT-2.0 stainless steel spokes. Front wheel features an Origin8 sealed system hub and see-through axle. Accepts all 27 x 1 1/8, 27 x 1 1/4, and 27 x 1 3/8 tires. Rims accept Presta valve stems or we'll be happy to drill the valve hole for schrader tubes. Both valve types are reviewed in the BikemanforU Instructional Video above. Enjoy a smoothly spinning ride.