1,under water treadmill 2,home treadmill 3,commercial treadmill 4,2.5HP motor How to choose suitable your treadmill 1. Treadmill Motor and Horsepower2. Treadmill Stability and Smooth Ride3. Treadmill Workout Features4. Noise and Space5. Treadmill Bargains and Alternatives6. Folding Treadmills vs. Non-Folding treadmill