The Absolute Black MTB Oval 104 BCD Chainring is designed for any cranks that use 104bcd mounting interface. This is the most common mounting standard for Shimano and other 4 arm cranks. Absolute Black MTB Oval 104 BCD Chainring Features Finest design to provide excellent weight to strength ratio One of a kind special oval shape (Patent Pending) 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 Designed to handle mud and grass with easy Superb quality and great look. You will ride faster using ovals. If you keep using round ring then others will get quicker. Reduces stress on knees and helps to maintain your legs fresher for longer. You will not feel the oval shape at all.