. >> near san diego, california, katie walker is putting her newest tool. this para olympic hopeful is trying out prosthetics field. >> the difference is the little wrist unit. it actually pops off. >> all right. >> and actually, the handle goes right inside of here. so, it's supposed to, after i swing, after i follow through, you just pop it right off. >> then run? >> then start running. >> and rotate around. cool. >> for upper-limb amputease, gone are the days of hook and cable arms. in labs like this one at advanced arm dynamics outside dallas, texas. technicians work alongside therapists to custom design dreams. >> really cool to have an opportunity to see a patient, see what they need and actually do what they need, not just say, well, all we have is this. i'm sorry. here you go. so we get to be really creative. >> now, thanks to electronic add veeps, the technology brings patients closer to the experience of experiencing the hand mobility most of us take for granted. one of the most sophist cases, the ultra revolution allows users to move through a se