Convenience (I had problems sitting on my wallet when it was in my back pocket) and size reduction (surprising how little I actually had to carry around!). I bought these with the intention of sharing with my teenage son while teaching him how to use a wallet. Bad move. Plastic internals, aluminum case glued to it, the one I have in the photo is the last of the six I received in the package. The plastic button for opening was broken on all six. The hinge on the back is broken on each one too (it's plastic too). The aluminum body glued to the plastic interior bends so easily. In a way, that's good as it fits in my pocket. I will never buy them again and will try another RFD wallet instead: https://www.amazon.com/gp/product/B07GJK7XSV/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1