Venture farther and stay warmer with the PhD® Outdoor Heavy Crew. Heavy cushioning and the power of itch- and stink-free ZQ-Certified Merino wool help keep your feet warm, dry, and comfortable whether you’re out on a multi-day trek or trudging through the snow. Featuring Indestructawool™ technology for ultimate durability in high wear areas, the 4 Degree™ elite fit system for a dialed fit, and our signature Virtually Seamless™ toe for extraordinary comfort in any trail shoe, this heavy-duty, technical outdoor sock can handle anything you can. And more.