Designed to fit SRAM cranksets with removable spiders. Its proprietary design has an ovality of 10% and a timing of 112 degrees after top dead center which provide the beneifits of an oval ring such as greater rear wheel traction without the traditional downsides of oval rings.0mm offset is designed for BB30 short spindle cranks (49mm chainline). Elliptical rings provide smoother, more efficient pedal rotation, which means better traction. Drop-Stop chainrings are designed for use with 1x9, 1x10, 1x11 and 1x12 drivetrains. Compatible with all 10-, 11-, and 12-speed chains, with the exception of 12-speed chains. 12-speed chains require the use of Wolf Tooth's 12-speed specific chainrings. If using a 9-speed drivetrain, use a 10-speed chain, which will provide a.