SHIMANO TOURNEY RD TY300 6S 7S Speed Rear Derailleur MTB Bicycle Part. Shimano Tourney RD-TY300 6 / 7 Speed Rear Derailleur. Shimano model: Tourney RD-TY300. SIS rear index shifting. Colour: Black. Can be used for either: 6 / 12 / 18 speed systems or 7 / 14 / 21 speed systems.
