The RaceFace Aeffect R crankset offers enduro-rated strength in a lightweight XC-style package making it a solid and dependable crankset choice. Please note that the chainring is sold separately.Its forged 7050 AL construction optimizes stiffness without added weightThe Aeffect R features the versatile CINCH system for plenty of interchangeable spider options (chainring and spider sold separately)Can run aluminum or steel CINCH direct mount chainrings (sold separately)Boost compatible 24mm EXI interface spindle TECH SPECS table{border-collapse:collapse;width:100%;} td{text-align:left;padding:8px;font-weight:350;} tr:nth-child(even){background-color:#f2f2f2} th{background-color:#eb212e;color:white;text-align:left;padding:8px;} .desc .specs-heading{font-size:24px;font-weight:600;padding-top:35px;border-top:3px solid #f0f0f0;display:inline-block;border-bottom:4px solid #eb212e;width:142px;margin:0;} Rings Sold Separately Number of Chainrings No Rings, No Spider Included Chainring BCD Direct Mount CINCH Chainline/Hub Compatibility 141/148 Boost Hubs Color Black Crank Length (mm) 165 Crank Intended Use Mountain BB Included No Pedal Spindle 9/16" Spindle Interface Type RaceFace EXI Defined Color Black keyword search RXC137 Size 165Mm