P/N: Y1LD98140. Deore : FC-M590 / FC-M591 - 9-Speed Chainsets (48T). Compatible With Shimano Chainsets SLX : FC-M670 - 10-Speed Chainsets (48T). Compatible with Shimano chainsets only! Shimano Deore FC-M590 / FC-M591 plastic chain guard for 48t outer chainring.
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