Shimano 7 Speed MF-TZ500-7 Index 14-28 Freewheel Block Screw-On Cog MTB. Shimano tourney MF-TZ500-7 7-speed screw-on freewheel that fits onto a multi-speed hub. One X Screw On Freewheel. Number of teeth on each cog are; 14, 16, 18, 20, 22, 24, 28 (smallest to largest).
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