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We reinvented long underwear with insulating Thermolite® technology and a micro-waffle texture for warmth without the weight.
You'll find a form-fitting base layer that sits close to your skin without the stuffed feeling of traditional thermal underwear. Built for winter layering under any outfit, WARMKNIT delivers genuine warmth through advanced insulation rather than excess fabric, keeping you comfortable for months of cold weather.
Men's Underwear & Briefs
| US Size | Waist (in) | Hip (in) |
|---|---|---|
| S | 28–30 | 34–36 |
| M | 31–33 | 37–39 |
| L | 34–36 | 40–42 |
| XL | 37–39 | 43–45 |
| XXL | 40–42 | 46–48 |
Men's Tops, T‑Shirts & Sweatshirts
| US Size | Chest (in) | Shoulder (in) | Sleeve Length (in) |
|---|---|---|---|
| S | 35–37 | 17–18 | 32–33 |
| M | 38–40 | 18–19 | 33–34 |
| L | 41–43 | 19–20 | 34–35 |
| XL | 44–47 | 20–21 | 35–36 |
| XXL | 48–51 | 21–22 | 36–37 |
Men's Pants & Bottoms
| US Size | Waist (in) | Hip (in) | Inseam (in) |
|---|---|---|---|
| 28 | 28 | 34–35 | 32 |
| 30 | 30 | 36–37 | 32 |
| 32 | 32 | 38–39 | 33 |
| 34 | 34 | 40–41 | 33 |
| 36 | 36 | 42–44 | 34 |
| 38 | 38 | 45–47 | 34 |
| 40 | 40 | 48–50 | 35 |
Men's Coats, Jackets & Outerwear
| US Size | Chest (in) | Shoulder (in) | Sleeve Length (in) |
|---|---|---|---|
| S | 36–38 | 17.5–18.5 | 33–34 |
| M | 39–41 | 18.5–19.5 | 34–35 |
| L | 42–44 | 19.5–20.5 | 35–36 |
| XL | 45–48 | 20.5–21.5 | 36–37 |
| XXL | 49–52 | 21.5–22.5 | 37–38 |
Men's Socks (Shoe Size)
| Sock Size | US Men Shoe Size |
|---|---|
| S | 6–8 |
| M | 8–10 |
| L | 10–13 |
| XL | 13–15 |
Backpacks & Men’s Accessories
| Size | Dimensions (H × W × D, in) | Capacity |
|---|---|---|
| Small | 16 × 10 × 5 | 18‑22L |
| Medium | 18 × 12 × 6 | 24‑28L |
| Large | 20 × 13 × 7 | 30‑35L |
* All measurements are in inches. Measure over light clothing for accuracy.
* If you are between sizes, we recommend sizing up for a more comfortable fit.
* Actual garment fit may vary slightly by style, fabric stretch and cut.
We reinvented long underwear with insulating Thermolite® technology and a micro-waffle texture for warmth without the weight.
You'll find a form-fitting base layer that sits close to your skin without the stuffed feeling of traditional thermal underwear. Built for winter layering under any outfit, WARMKNIT delivers genuine warmth through advanced insulation rather than excess fabric, keeping you comfortable for months of cold weather.
- Insulating Thermolite® technology
- Micro-waffle texture
- No-roll waistband
- Stay-put ankle cuffs