THESE RINGS ARE FOR USE WITH SHIMANO 110 BCD ASYMMETRIC 4-BOLT CRANKS. PATENTED DROP-STOP ® WIDE-NARROW TOOTH PROFILE FOR MINIMISED DROPPED CHAINS PERFECT FOR 1X SETUPS MACHINED IN-HOUSE AT WOLF TOOTH'S HQ IN MINNESOTA, USA BEAUTIFUL ANODISED FINISH COMPATIBILITY THESE RINGS ARE FOR USE WITH SHIMANO 110 BCD ASYMMETRIC 4-BOLT CRANKS. COMPATIBLE WITH DURA ACE 9000, ULTEGRA 6800, 105 5800, TIAGRA 4703, AND TIAGRA 4700 SIZES 40T AND LARGER ARE COMPATIBLE WITH DURA ACE 9100, ULTEGRA 8000, AND 105 R7000 BUT A SLIGHT MODIFICATION IS REQUIRED DUE TO A CHANGE IN THE CRANK ARM PROFILE. THE 38T CHAINRING WILL NOT WORK FOR THIS MODIFICATION. CLICK HERE TO REVIEW THE PROCESS FOR THE MODIFICATION, WHICH TAKES ABOUT 5 MINUTES TO PERFORM. THIS CHAINRING MOUNTS IN THE BIG RING POSITION OF THE CRANKS BUT IS OFFSET INWARD FOR PERFECT CHAINLINE. THE STOCK 2X BOLTS WILL NOT WORK. YOU WILL NEED 6MM BOLTS WHICH ARE OPTIMIZED FOR SINGLE RING MOUNTING, AND AVAILABLE SEPARATELY FROM WOLF TOOTH. WOLF TOOTH'S PATENTED DROP-STOP ® WIDE/NARROW TOOTH PROFILE FOR THE ULTIMATE CHAIN RETENTION AND MUD SHEDDING ABILITY FOR 1X9, 1X10, 1X11 AND 1X12 DRIVETRAINS (INCLUDING SRAM EAGLE) COMPATIBLE WITH ALL 10-, 11-, AND 12-SPEED CHAINS EXCEPT SHIMANO 12-SPEED CHAINS. IF USING A 9-SPEED DRIVETRAIN USE A 10-SPEED CHAIN (SHIFTS AND WORKS WELL ON A 9-SPEED DRIVETRAIN AND FITS THE RING TIGHTER FOR BETTER CHAIN RETENTION). CHAINLINE - 47.5MM