The Kangoo Jumps Black/Orange Exercise Boots are the KJ XR3 model, they are suitable for both indoor and outdoor use. These Kangoo Jumps are available in medium size for men's 6-8 and women's 7-9. I don’t use them any more, they were used for about 9 months once or twice a week and then stored. They are a lot of fun and a great way workout option.