Choose the Yzy Bst if you want more support and comfort. Innovated by and leading chemical company BASF, the Boost is a revolutionary cushioning system which "bsts" your speed and energy. The Yzy Sldes "Earth Brown" is a great option for when you want to ditch the sneakers. Made with EVA foam, the slides comes in a earthy brown tone. The ridged outsole provides support and stability, making the slides perfect for any occasion.