I swore by leather bifolds as the best option for an unobtrusive men’s wallet. When my last one was beginning to wear out, I looked around at other more minimalist options. The Butterfly Wallet stood out because of its low price and very small footprint. This isn’t like the velcro-closure nylon wallet that you had as a kid, it’s a simple arrangement of credit card slots and a place to put cash.
I was skeptical because I thought the trifold design was inherently less efficient, requiring bills to be tripled over in thickness. That turns out to be a non-issue and my Butterfly Wallet with 14 bills and 6 credit card like objects is about 1/2 inch thick. As a bonus, there is now little enough material around my Metro SmarTrip card that I can scan it without removing it from my wallet or even the wallet from some pants!
I used to remove my wallet from my rear pants pocket when I got in the car to take a long drive or even just at the office, and I’m certainly now George Costanza. My wallet is now so small and light that the biggest problem is thinking that I’ve lost it because it’s not a notable bulge on my buttock.