While sifting through her Instagram feed earlier this year, Ava Nirui, the artistic director of youthful Marc Jacobs sub-brand Heaven, stumbled on Nong Rak’s striking knitwear and knew she had found her next collaborator. The result was a small, 20-piece drop, including balaclavas, leg warmers and berets, which generated outsized media impact for the fledgling Thai-American knitwear label. Nong Rak’s knits are made from vintage yarns, using nothing more complex than a manual knitting machine.