Every closet needs a stellar waffle-knit shirt, and this one from adidas cuts no corners. With a ribbed polo collar and contrasting ribbed armholes, it packs in classic details that give it a crisp, clean look. A mix of cotton and elastane keeps comfort going strong, and a slit hem invites you to layer up and move freely. And if you're getting a '70s vibe, there's a reason: We designed this one based on archival concepts from that influential decade.