... , steel frame and fork, 42T Chainwheel & Crank, Sunrun 7 speed derailleur, with fender and carrire 20"Steel folding bicycle, steel frame ... and fork, 42T Chainwheel & Crank, Sunrun 7 speed derailleur, with fender and carrire20" 6 speed alloy folding bicycle(WL ... " x 1.75" A/V 10) bicycle derailleur: Sunrun, 7 speedOur supplier products:folding, folding bikes, folding bicycles, folding bike ...