I forgot about the clip. Those came out right when I started at Nike in the early 2000’s. They were the first shoe I bought from the employee store. Designed by Eric Avar. I loved those things. I think the original thought was to be interchangeable, but to get it to function correctly as a shoe, the mechanical lock was so tight that it was incredibly difficult to disassemble. Plus there was no retail vehicle for just buying uppers or sole units because .com retail was not nearly as developed as it is now.