This is the therapeutic model. It could be taken outside, it has 6 locking caster wheels, the full frame and seat. Similar, but different, than this one: https://www.glidecyc le.com/product/x-runner/. It could be taken outside for a walk or locked in place for therapy, rehab, over a treadmill or petals for cycling. It has many options. It easily comes apart and assembles for moving and storage. Weight-free running!