One of the best flip flops I have worn (if not the best)!!!
They are very comfortable, ergonomic, and most importantly, they do not slip at all!!! (neither the flip flop on the floor, nor the foot inside the flip flop)

I bought 2 pairs for my husband and my son. Excellent! Anatomical, made with very good quality materials, doesn't make the foot sweat, the sole is soft, it's a shame they don't come in women's sizes!