4-arm, for MTB, Mod. 17, for 2x10-speed, 104 / 64 mm BCD, 7075 T6 aluminium, black CNC, 100% compatible with Shimano XTR FC-M980 technology HT3 7075-T6 aluminium chainrings with a titanium oxide electro-ceramic coating. This exclusive coating offers an ULTRA-HARD surface for a long service life (Hardness: 1.5 to CT2). The friction and abrasion coefficient has been significantly reduced (0.2-0.3) and offers noise reduction as well as excellent corrosion resistance. Number of teeth 22 Type of item mounting 4-hole Field of application MTB Main colour black Bolt circle diameter 64 mm Rear gear steps 2-speed, 10-speed