The Cycleops Mag+ Turbo Trainer With Shifter lets you manually adjust the resistance in your trainer without having to get out of the saddle. The Handlebar mounted shifter lets you select how much resistance you want & easily vary it to simulate sprints & climbs & for warm up & warm down periods. The Cyclops Mag+ Trainer will work with all common adult bike wheel sizes & with most road & mountain bike frames that use a quick release axle. Thru axle adaptors are available separately. Although the Mag+ is not a ‘smart trainer’ you can hook it up to virtual training software like Zwift using the Cycleops Speed Sensor (sold separately). This will allow you to send data to programs like Zwift but not to get feedback in return. Features Magnetic resistance unit provides a quiet & frictionless ride. Linear resistance boosts workout intensity to match each pedal stroke & gear click. Comes with convenient, adjustable handlebar- mounted shifter. Noise level at 20 mph is 70-74 decibels. Eccentric leveling feet allow for easy adjustment on uneven surfaces. Precision-machined alloy roller reduces tire wear & slippage. Comes on the Cycle Ops foldable Classic frame with spring loaded, bolt-action lever. Adjust tire fit to resistant unit with a convenient turn knob. 2" resistance unit roller allows for 650b, 700c, 26", 27" & 29" wheel sizes – up to a 2.0 tire. This trainer is designed to fit common road & mountain bike frames with included steel quick release skewer & has three settings for rear dropout spacing: 120mm, 130mm & 135mm. Trainer tire recommended. Compatible with virtual training apps. All of our trainers are tested to the combined weight (rider & bike) of 300 lbs. Optional thru-axle adapter available for 142x 12mm & 148x 12mm bikes.