Size: 13T, 14T, 15T, 16T, 17T, 18T. • 16T: 14 g / 0.80 oz. Box One Single-Speed Aluminum Cogs are 7075-T6 aluminum alloy. It's designed to fit Shimano™ compatible cassette hubs and has a 5mm wide inner base, giving a more solid interface with the cassette body.
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