CycleOps Magneto Cycling Trainer The world's first magnetic trainer with progressive resistance. Magnetic resistance unit provides a quiet and frictionless ride. Precision-balanced zinc alloy flywheel features magneto technology. Promises secure tire to resistance unit fit with our unique clutch knob. Noise level at 20 mph is quiet 66-68 decibels. Made in Madison, WI, USA Lifetime warranty Not compatible with 29'ers Mag trainer with progressive resistance Designed with PowerBand technology that allows resistance levels to vary with cadence or gear shifts Quick load cam lever for easy resistance unit attachment