Blackspire recognition cassette expander sprocketgreat addition to your 1x drive train with just the swap of one cog to your existing 10 speed cogset increases range to your drive train without breaking the bank pair this with a blackspire snaggletooth wp ring up front and your ready to ride features for shimano fc m782 fc m672 fc m622 and fc m612 96bcd cranks for use with 10 speed drivetrains material cncd 7075 t 6 includes spacer and longer btension screw finish anodized with laser