Rainbow Willow Flip-Flop Sandals The Willow sandal by Rainbow features an added braid on the 3/4" wide nubuck leather straps, which are both comfortable and feminine. Willow is on a double layer construction, giving you excellent arch support and a little extra cushioning (and height!) in the heel. As this sandal breaks in, it also molds to your foot. The longer you have them, the better they feel! Leather uppers/leather footbed. Imported.