sram 30t chainring sram 30t eagle technology x-sync 2 sram 30t sram 30 t chainring sram 30t oval chain ring sram 30t chainring t type sram 30t 94 bcd x 4-bolt 11/12-speed x-sync2 eagle chainring, black sram 30t 104bcd sram 30t crankset sram 30t eagle technology x-sync