The Absolute Black Boost 148 Direct Mount Oval Chainring is the one and only absoluteBLACK premium Sram compatible Direct mount BOOST148 1X Oval chainrings, and are designed for GXP and Long BB30 spindle cranks. Chainring is dedicated for Boost148 bikes ONLY. Converts a regular Sram crank into a Boost specific setup. (3mm offset). They are also 100-percent optimized for Eagle. Compatibility: SRAM XX1, XX1 Eagle, X01, X01 Eagle, GX Eagle, X1, X0, X9, X7, S2210, S1400 and Truvativ AKA cranks. GXP and Long spindle BB30. BOOST148 bikes ONLY. 9, 10, 11 and 12spd Eagle compatible. Absolute Black Boost 148 Direct Mount Oval 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.