The Adidas Prime X Strung is a long distance neutral running shoe. This shoe is an absolute blast to run in. Light and springy, it uses Adidas Lightstrike Pro technology—their most innovative and advanced foam. Unisex Size 7. I wear a Women’s 8 and men’s 6.5 and these fit perfectly. These shoes are tough to find and are sold out in most colors and sizes without paying a huge markup.