AeroSkyn™ is our patented blend of 85% nylon-based microfibers and 15% Lycra, crafted to deliver top-tier performance and comfort. This game-changing fabric is designed to keep you moving with confidence. Here’s what makes it stand out:

• Next-Level Comfort: Super-soft microfibers and stretchy Lycra feel like a second skin, adapting to your every move and keeping you comfy all day.
• Sweat-Busting Tech: Grooved fibers wick away sweat fast, so you stay dry during tough workouts. Hollow fibers trap warmth when it’s chilly, keeping you just right.
• Support That Moves With You: Just-right stretch cuts fatigue and gives you freedom without feeling tight, perfect for any activity.
• Stay-Fresh Design: Built-in odor-fighting fibers keep sweat and smells in check, so you feel fresh no matter how hard you push.
• Planet-Friendly & Safe: Made with eco-friendly processes, AeroSkyn™ is hypoallergenic, metal-free, and free of nasty chemicals, keeping you and the environment safe.

AeroSkyn™ is UnderXLabs’ promise of innovation, comfort, and responsibility, built for guys who demand the best in every moment.

To keep your UnderXLabs apparel, powered by AeroSkyn™, in top shape, follow these simple care tips:

• Standard Care: Machine wash on cold (30-40°C or 85-105°F) with a mild detergent. Use a gentle tumble dry on low heat for easy maintenance.
• Max Longevity: Hand wash gently in cold water (30-40°C) and air dry to preserve the fabric’s performance and fit over time.

Proper care ensures your UnderXLabs gear stays comfortable, supportive, and ready for every move.

UnderXLabs redefines men’s underwear as performance-driven luxury, crafted for those who value quality, design, and an elevated lifestyle. Our five distinct cuts, powered by AeroSkyn™, are tailored to fit your needs and style:

• Zero Brief: Sleek, minimalist design with no visible lines. Offers robust support like our Classic and Sport Briefs but feels barely there. Ideal for fitted or tailored outfits.
• Classic Brief: Timeless and versatile with full coverage. A go-to for everyday wear, blending traditional fit with seamless adaptability to any wardrobe.
• Trunk: Modern, fitted look with a shorter inseam. Perfect for less coverage without sacrificing support, designed for enhanced mobility.
• Boxer Brief: Classic, all-purpose cut for most body types. Longer inseam than the Trunk for extra coverage, balancing comfort and function for daily wear.
• Long Boxer Brief: Extended inseam for maximum coverage and support. Tailored for active pursuits or layering, ensuring a secure, friction-free fit.

Each cut is engineered with precision for specific lifestyles and occasions, delivering comfort, support, and confidence. Need help choosing? Let us know.

With AeroSkyn™’s body-adaptive technology, our fabric effortlessly molds to your unique shape for a custom-like fit. Most customers find their true size delivers the best comfort and performance—designed to feel like it was made just for you.

Get the Perfect Fit Easily

Our side menu and product pages feature:

• A straightforward waist size chart for quick reference.
• A detailed 3D measurement guide for precise sizing.

Customers rave that our sizes fit true, so you can choose with confidence.

Need Help?

• Email us at support@underxlabs.com.
• Check out the “Connect” section in our footer menu.

We’re here to help you nail the perfect fit for your performance essentials.

UnderXLabs products are crafted in top-tier facilities across the globe, designed in the USA and brought to life through a trusted global supply chain. Our manufacturing partners in countries like China, Vietnam, and Bangladesh adhere to strict national regulations and align with our core values of quality, sustainability, and ethical production. We carefully select suppliers and materials to ensure every piece meets our high standards, delivering performance and responsibility in every stitch.

UnderXLabs redefines men’s underwear as performance-driven luxury with AeroSkyn™, a patented 85% nylon microfiber and 15% Lycra blend. Unlike budget brands’ short-staple cotton that tears or pills quickly, or mid-tier synthetics with outdated tech, AeroSkyn™ delivers grooved fibers for instant sweat-wicking, hollow-core insulation for all-day comfort, and antibacterial properties for lasting freshness. Seamless 3D knitting ensures a friction-free, second-skin fit, outlasting competitors’ basic designs. Our eco-friendly production guarantees sustainability and durability. Plus, our 365-day Quality Guarantee and 30-Day Best Pair Guarantee—allowing returns or exchanges on one pair within 30 days and full refunds for quality issues within a year, including shipping—make every purchase risk-free. This premium price reflects unmatched craftsmanship, innovative materials, and our confidence in delivering lasting value.

UnderXLabs is pleased to accept the following credit cards as convenient means of payment: American Express, Mastercard, Visa, JCB, and PayPal. In order to ensure that your shopping experience is simple and secure, order and payment transactions are processed using a secure server. Please note that the individual who submits the order must be the cardholder whose name appears on the credit card.

To check the status of your order, please visit the Thack Your Order page on our website.

If you purchased your order online while logged in, you may also see more information through your My UnderXLabs account.

Status updates regarding your order will be sent to your email; if you have not received these emails, please note that order confirmation emails may be caught in a spam or deleted folder; these emails usually do not appear in general email searches and may only appear when specifically searching your spam or deleted emails folders. We recommend searching these additional email sections with your order number to see if your emails may be in these folders.

Should you need to cancel or change your order, please Contact Us as soon as possible; we will make every effort to accommodate your request.

Please note that we cannot guarantee that your order may be adjusted once it has been submitted.

Shipped orders may not be cancelled or modified; however, you may return your item subject to our Terms of Use.

Please double-check the email address you used and spam folders. The confirmation may have gone to an email address you don’t frequently use. If you are still unable to find the order confirmation, it is likely the order did not go through.

Most credit cards are declined because the billing address you entered does not match the address your bank has on file, incorrect CVV or wrong zip code. Please be sure to double check this info before proceeding. You can always try using a different type of payment like Paypal.

We offer three convenient shipping options:
• Standard Shipping: 5-7 business days, $6.99
• Expedited Shipping: 3-5 business days, $10.99
• Express Shipping: 2-3 business days, $17.99
Free shipping orders default to Standard Shipping. Delivery times are estimates and may vary due to unforeseen circumstances. Track your order anytime on our “Track Your Order” page.

All orders ship from our Los Angeles facility. We currently don’t offer in-store pickups or in-person support, but our online experience is designed for ease and reliability.

Most orders ship within 1-2 business days.
Orders placed before 1:00 PM PST on business days typically ship same-day; evening orders ship the next business day. Weekend orders ship the following Monday. You’ll receive a Shipping Confirmation email once your order is on its
way. If it hasn’t shipped after four business days, contact us at support@underxlabs.com.

Your UnderXLabs order arrives in our signature black package. For added protection, we use discreet, durable outer packaging to ensure your items arrive in pristine condition.

Currently, we ship only to U.S. addresses. International shipping is coming soon—stay tuned for updates!

Order confirmations arrive within minutes, and shipping confirmations within 48 hours (weekend orders may ship Monday). If you don’t see them:

• Check your spam/junk folder.
• Verify you’re checking the correct email inbox.

Still missing? Contact us at support@underxlabs.com, and we’ll resolve it quickly.

If your order is incorrect, compare it to the shipping invoice in your package. For wrong items, missing items listed on the invoice, or someone else’s order, contact us at support@underxlabs.com, and we’ll make it right. If a missing item isn’t on the invoice, check your Shipping Confirmation email for a note about inventory issues—we’ll have refunded you automatically. We’re sorry for any mix-up and are here to help!

We offer a 30-day return policy. You have 30 days from delivery to request a return or exchange for one opened pair of AeroSkyn™ underwear. For first-time orders with multiple pairs, we recommend trying one pair to confirm sizing before opening others. Returns are processed within 48 hours of receipt and inspection. See our Return & Exchange Policy for full details.

To return or exchange your purchase:

1) Contact us at support@underxlabs.com for a return authorization number, which must be noted on the included return form.

2) Securely pack the item to prevent damage during transit.

3) Ship the package to our designated address via any courier, keeping tracking info for reference (a photo of the label works great).

Once received, items undergo quality inspection. Approved returns or exchanges are processed within 5-7 business days (longer during holidays). If an item doesn’t pass inspection, we’ll contact you with next steps. Visit our Return & Exchange Policy or Terms of Use for more info.

After receiving your return, we inspect it within 48 hours. Approved refunds or exchanges are fully processed in 5-7 business days, though holidays may extend this timeline. Check our Return & Exchange Policy or Terms of Use for details.

Customers are responsible for return shipping costs unless the return is due to our error (e.g., wrong or defective item). Contact us at support@underxlabs.com to initiate the process and confirm eligibility.

We are proud to be OEKO-TEX STANDARD 100 Certified, a globally recognized benchmark for safety and sustainability in textiles. This certification ensures that every component of our products—down to the threads and dyes—has been rigorously tested for harmful substances and meets the highest safety standards.

Being OEKO-TEX STANDARD 100 aligns with our commitment to creating apparel that is not only performance-driven but also safe, environmentally responsible, and respectful of your health and well-being. At UnderXlabs, quality and integrity are at the heart of everything we do.