front derailleur, 3-speed bicycle derailleur compatible with 31.8 / 34.9mm tube diameter for MTB mountain bike (7/8/9 speed)

HOUSON front derailleur, 3-speed bicycle derailleur compatible with 31.8 / 34.9mm tube diameter for MTB mountain bike (7/8/9 speed)

Single/6/7/8/9/10/11/12 Speed Bike Chain, Bike Chain for Road Mountain Racing Cycling (6/7/8 speed)