Modal vs Supplex Underwear Fabric: What's the Difference?

Quick answer

Choose Supplex® when you want stretch that holds its shape, moisture wicking, and firm pouch support for sport or long active days. Choose Modal when you want a softer, silkier feel and naturally breathable comfort for desk days, travel, and evenings out. Both are available in the same Cocksox cuts, so fabric is the real decision, not the silhouette.

Cocksox makes the same brief and boxer shapes in more than one fabric, which means the fabric is often the only thing standing between you and the right pair. Supplex® and Modal are the two you'll see most, and they behave very differently against skin.

This comparison sticks to what the catalog actually states about each material and the products that use them, then translates that into real-world choices: gym bag, office chair, or a night out.

How the two fabrics actually differ

Supplex® is a performance fabric. Cocksox describes it as holding shape, supporting your boys, and wicking moisture away, which is why it anchors the sports and everyday briefs. In practice that means less sag through a long day and a drier feel when you're moving.

Modal is a natural, sustainable fabric that Cocksox calls soft, breathable, and moisture-wicking. It feels silkier against skin and is the choice when comfort and a lighter hand matter more than compression or structure.

• If you sweat heavily or train often, lean Supplex®.
• If you sit for long stretches or run warm indoors, lean Modal.

Support and shape retention

Supplex® is the firmer option. The CX01 Supplex Brief uses the original Cocksox enhancing pouch in a fabric that holds shape, so the pouch keeps its structure instead of relaxing after a few hours. The CX76N Supplex Sports Brief adds robust piping and a butt-hugging seamless wrap-around back for active movement.

Modal keeps the same pouch design but with a softer, more fluid hand. The CX01MD Striped Modal Brief carries the original high-cut brief cut in deluxe Modal, and the CX16MD Vicennial Modal Bikini Brief pairs naturally breathable Modal with a thigh-high cut and full front and back coverage.

• Pick Supplex® if you want the pouch to feel locked in place.
• Pick Modal if you prefer support that moves quietly with you.

Breathability, drying, and day-to-day feel

Both fabrics wick moisture, but they read differently on the body. Supplex® dries quickly and feels technical, which suits commutes, workouts, and humid days. Modal breathes naturally and feels cooler and smoother, which suits long seated days and warm indoor environments.

Neither fabric is described as a compression fabric, so if you need medical-grade compression, look elsewhere. Within the Cocksox range, the trade-off is structure versus softness, not performance versus no performance.

• Two pairs in different fabrics covers most weeks better than three of the same.
• Wash according to the care label to protect shape retention.

Prints and cuts change with fabric

Fabric choice also decides which designs you can buy. The CX12DD Supplex Boxer carries the Day of the Dead Calavera print in a boxer cut, while the CX12MD Vicennial Modal Boxer uses silky Modal with the exclusive Vicennial world-map print marking 20 years of Cocksox.

So if a specific print or cut is the priority, check which fabric it's made in first. If the fabric is the priority, the brief and boxer shapes are both available across the range.

• Limited prints tend to live in one fabric, so decide fast if a design matters to you.

Trade-offs to weigh before you buy

• Structure vs. softness: Supplex® holds shape and keeps the pouch firm; Modal feels silkier and drapes more softly. Choose Supplex® for support, Modal for comfort.
• Performance drying vs. natural breathability: Supplex® wicks moisture and suits sweat and movement; Modal breathes naturally and suits warm, seated days. Match the fabric to your most common environment, not your best-case one.
• Print availability vs. fabric preference: Some prints, like the Day of the Dead Calavera and the Vicennial world map, are tied to one fabric and cut. Decide whether the design or the fabric matters more before ordering.

Cocksox products that show the difference

• CX01 Supplex Brief: Made from Supplex® fabric that holds shape, supports your boys, and wicks moisture away, with the original Cocksox enhancing pouch. The clearest starting point if you want firm pouch support and shape retention through a full day.
• CX76N Supplex Sports Brief: High-performance Supplex® with the Cocksox contour pouch, a butt-hugging seamless wrap-around back, and robust piping. Built for active sportsmen who want freedom of movement without losing support.
• CX16MD Vicennial Modal Bikini Brief: Naturally breathable Modal in a thigh-high bikini cut with full front and back coverage, in the exclusive Vicennial 20-year print. The pick when you want a softer, lighter feel plus a commemorative design.
• CX01MD Striped Modal Brief: The original high-cut CX01 brief in deluxe Modal with a knitted striped pattern; Modal is soft, breathable, and moisture-wicking. Keeps the familiar CX01 cut while swapping structure for silkier comfort.

Which fabric should you pick?

Best for

• Gym sessions, sport, and long active days where shape retention and moisture wicking matter
• Anyone who wants the firmest pouch support in the Cocksox range

Not for

• Shoppers who want the softest, silkiest feel against skin
• Anyone prioritising a specific Modal-only print or design

Start with Supplex® if your days are active and you want the pouch to stay put, and start with Modal if comfort and breathability come first. Both use the same Cocksox pouch and cut philosophy, so you can switch fabrics without relearning the fit.