lots of choices there. coaster brake S2C duomatic 6061 aluminum shell, or S2 no brake with freewheel, or B2C black duomatic steel shell and cogs from 13-22T these are one gear @ 100% direct drive and other gear @ 138% overdrive ( +38% ) unlike the old Bendix kickback that shifted down to a lower gear when you stopped. good though. just gotta pick the front and back gear sizes that work for you.