The Original one and only absoluteBLACK Premium, Shimano 12 speed compatible Direct mount 1X Oval traction chainrings are designed for XTR M9100, XT M8100 & SLX M7100 cranks. They feature the exact same excellent oval shape as rest of our oval chainring portfolio. This new type of direct mount chainring will make your Shimano crank looking great and perfectly mesh with new Shimano 12spd chain. This particular chainring will ONLY work with CN-M9100 chain due to different thickness of the teeth. Compatibility Fits to Shimano XTR M9100 , M9120, XT M8100, M8120, M8130 , SLX M7100, M7120, M7130 and FC-MT900 cranksets. Works ONLY with CN-M9100 chain. Material CNC machined 7075 Txxx Aluminum. Long-lasting construction! Type II anodizing Chainline Perfect 51mm Ovality Optimized to each size separately. Range: 10.2-14.4% and Timing of 110.5-116.3° after TDC (top dead center) Patent Pending It's a Direct Mount chainring so please use original lockring to mount it on the crank. Always use a new chain with a new chainring If you wish to check for frame clearance with new oval ring, below you can find measurement of biggest dimension of the oval (tip to tip of tooth): 28T: 127mm ; 30T: 134mm ; 32T: 143mm ; 34T: 151mm ADVANTAGES OF OUR SPECIAL OVAL CHAINRINGS *We mastered our oval chainrings to perfection, so you can get best possible advantage from the oval/elliptical shape. *Finest design to provide excellent weight to strength ratio *One of a kind special oval shape (Patent Pending) *Greatly improves traction and climbing abilities *Unique Patent Pending narrow-wide teeth profiles to keep your chain in place for minimum 12 months! *Special 3D teeth machining for ultimate mud relief decrease wear and noise dramatically *All rings have built in threads for easy of mounting and reduction in weight *Superb quality and great look. *You will ride faster using ovals. If you keep using round ring then others will get quicker. *You will not "feel" the oval shape at all *Reduces stress on knees HOW TO MOUNT ABSOLUTEBLACK OVAL CHAINRING Using Hollowtech II BB Removal Tool (like BBB BTL-116 ), carefully open the lockring that holds the chainring on the crank(normal threads). Once the lockring is removed, take off old chainring, re-grease the splines on the crank. Place new oval chainring with convex side to the crank. Chainring/crank has special splines that only fit one way. Close the lockring to 35-50Nm of force. Chainring is only compatible with XTR CN-M9100 chains. Using other chains may cause chain to drop very easily from the chainring due to thinner than usual teeth. It is ideal for 1x 12spd. Oval (elliptical) chainring does not compromise the work of clutch mechanism in rear derailleur(video at the bottom). It also does not require chain tensioner when using in singlespeed application. Riding out of saddle on the uphill will become more pleasant. Ovality of the chainring is in range of 10-14% (dependent on size) and feels perfectly round when riding. These chainrings also help you to recover after knee injuries as pedaling becomes smoother and less exhausting. It is the most advanced oval chainring currently on the market. Chainguide needed? No. But if you want one then chain guide should have 2 teeth more capacity than nominal oval ring size. Designed in UK. Manufactured in Poland (EU). The World's best oval chainrings for Shimano.