Performance boxer briefs cut from technical fabric and built for an active lifestyle
Proof’s Heathered Interval Boxer Brief is designed to be worn all day—and even longer when you need to—with fabric that stretches even at your slightest movement and an anti-microbial finish that keeps it fresh and odor-free. Exceptional flexibility with both horizontal and vertical stretch ensures these briefs move with you in every direction, whether you're at the gym or on your daily commute. The incredible fabric, developed in conjunction with Japan’s Toray Industries, is not only soft and comfortable, but built to retain its shape with industry-leading shape recovery.
- Cut from a technical fabric developed specifically to create high-performing underwear you can rely on for an active lifestyle
- Low-power stretch feels like it isn’t stretching at all, but simply moving along with your body like a close-fitting base layer should
- Four-way stretch moves with you in every direction
- High stretch recovery means the fabric will never get baggy and loose, no matter how much you wear and wash
- Anti-microbial finish that fights odors and keeps things fresh, also prevents bacteria from degrading the fabric for a longer life
- Plush elastic waistband for comfort
- Four-way stretch fabric from Toray Industries of Japan
- 55% nylon, 27% polyethlene, 18% lycra
- The Heathered Interval Boxer Brief has a snug, next-to-skin fit
- Take your normal size in boxer briefs
- For the best personal fit, compare the measurements of one of your best-fitting boxer briefs to the garment measurements below
Garment Measurements
| XS | S | M | L | XL | XXL | |
|---|---|---|---|---|---|---|
| Waistband | 26½ | 28 | 29 | 30 | 31½ | 33 |
| Inseam | 4 ¾ | 5 | 5 ¼ | 5 ½ | 5 ¾ | 6 |
| Seat | 16 ½ | 17 | 17 ½ | 18 | 18 ½ | 19 ¼ |
All measurements are in inches.
Email us at [email protected] for sizing guidance or other questions.
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