Adidas ZX 2K Boost Shoes Crystal White - crystal white/true pink/matte silver Size US 7.5 The back of the shoes are white suede and do have some marks on them adidas FZ3900 Take it from us. There's something really fun about not just pushing past limits, but full-on jumping over them and not looking back. These adidas shoes fueled by the ZX legacy and inspired by the Artemis space mission embody that idea. Metallic details. An ultra-comfortable Boost midsole that pops through the semi-translucent cage.