The XT385 is designed to keep you motivated mile after mile. Our large 22″ x 60″ running surface and 3.5HP motor give you all the room and power you need for a comfortable workout. The top speed of 12mph and 15% elevation are sure to keep you challenged.The XT385 has the same options as the XT285 plus two user programs . up to 15% elevation capability . aluminum side rails . larger motor with wider belt . and frame uprights stability bar for a more solid feel. The XT385 connects to third party apps via Bluetooth FTMS and is Zwift App Compatible. This model is very appealing to someone that is a walker . at a transitional stage from walking to running . or a mid-level runner.