The adidas ZX 4000 4D “Black Onix” is a spring 2019 release of the retro-meets-future running shoe. The upper takes inspiration from the ZX 4000, a now-vintage performance adidas running shoe from the early 1990s, and updates it with a modern Primeknit construction while retaining the aesthetic of the original model. The upper sits atop adidas’ 4D midsole, which is an intricate 3D-printed sole constructed with cutting-edge technology named Digital Light Synthesis. The high-tech process uses light and oxygen to shape the structure of the sole. This colorway features a combination of black, grey, and bright red across the upper with the 4D sole in its signature light green shade.