I don't even know what mine are called, as they're pretty old...they're my Disney shoes, I have never used them except for when at WDW. I guess they're more of a sandal than a true flip-flop. It has two straps across the top, one near the toes and one mid-foot, to keep my foot planted in the shoe. It's also got a strap across the back of the heel for the same purpose. I find them MUCH better than a true flip flop where the back of your feet lift from the shoe with every step. These are the only thing I wear. I brought a pair of sneakers, but didn't use them once this trip.
Only problem I find is that my heel and my big toe will get really dry. My heel actually split open a tiny crack and my toes got really rough...but it was my own fault, I knew they were getting dry and didn't use lotion quick enough. Once I did, they were fine.