 This is one of the coolest kinds of prosthetic ankles that I literally cannot believe I am holding one of my own of right now. This is a bio-adapt ankle. It is made for things like snowboarding, weightlifting, biking. I was gifted one of these and broke down in tears on my state's news channel and live in front of hundreds of people outside of the function, which is gonna be amazing. Just look at how badass this looks. Tell me that you're not a little jealous. You just got a boring, neat leg right now. I would be. With a dual piston system, are you kidding me? I don't know what that is, but it sounds very cool. Jokes aside, this is an incredible gift and I cannot wait to try it out weightlifting this week. First, I gotta figure out how to use it because there are a lot of settings.