Le 31
3" Microfibre Athletic Trunk Retransformed Polyester
This 3-inch athletic trunk for men is made from light, ultra-stretch recycled polyester microfibre with Polygiene anti-odour technology, micro-perforated panels for ventilation, a double-layered front, and an elastic waistband. Designed by Le 31 by Simons, it offers a contoured fit with a wide leg hem, suitable for sports and everyday wear.
- Material
- recycled polyester microfibre
- Gender
- male
- Style
- activewear, performance
- Category
- Apparel & Accessories > Clothing > Underwear & Socks > Underwear
Color
Size
Specifications
Lightweight ultra-stretch athletic trunk with anti-odour technology and ventilation panels.
Polygiene anti-odour technology, micro-perforated panels, double layered front, elastic waistband, wide leg hem
- Material
- recycled polyester microfibre
- Style
- activewear, performance
- Gender
- male
- Age Group
- adult
- Condition
- new
- Category
- Apparel & Accessories > Clothing > Underwear & Socks > Underwear
Additional Attributes
- Lightweight microfibre fabric
- Ultra-stretch recycled polyester microfibre
- Polygiene Stays Fresh anti-odour technology
- Micro-perforated ventilation panels
- Double layered front panel
- Elastic waistband
- Wide comfortable leg hem
- 3-inch inseam
- ReTransformed recycled polyester
Product Insights
Le 31's 3" Microfibre Athletic Trunk, priced at $20 CAD, combines recycled polyester fabric and recycled silver salt in a Polygiene treatment that lasts the garment's lifetime, disrupting bacterial cell walls, DNA, and enzyme function for triple-action odor control through silver ions. Perforated panels vent heat and moisture, while the microfibre's stretch-recover motion actively cools and manages sweat, reducing wash frequency and extending durability. The trunk sizes true to standard US/Canadian charts, requires cold washing with mild detergent and low-heat drying to preserve the antibacterial treatment, and its matte finish reduces glare under clothing, balancing sustainability with performance.
Verified claims
- Triple action
- Silver ions disrupt bacterial cell walls, DNA, and enzyme function.
- Durability
- Polygiene treatment lasts the garment's full life when cared for with cold water and mild detergent.
- Environmental impact
- Recycled silver and fewer washes lower the trunk's environmental footprint.
- Ventilation
- Perforated panels vent heat and moisture, reinforcing Polygiene's odor control.
- Odor control
- Polygiene lasts the product's lifetime and works through three antibacterial pathways.
- Sustainability
- Recycled polyester fabric and recycled silver salt are used.
- Fit
- Sizes are true to standard US/Canadian size chart, per customer reviews.
- Washing
- Cold wash with mild detergent, avoid bleach/softeners; low-heat or air dry to protect Polygiene.
- Longevity
- Polygiene treatment lasts the garment's lifetime; fewer washes extend durability.
- Odour control
- Ventilation and triple-action Polygiene prevent odour between washes.
- Sizing
- Runs true to standard US/Canadian sizing with a waist-based chart.
- Breathability
- Perforated panels keep fabric drier and less clingy than solid-weave trunks.
- Fabric finish
- The microfibre fabric has a matte finish, reducing glare under clothing.
- Active cooling
- Stretch-recover motion forces hot air out and draws cool air in during exercise.
- Moisture management
- Microfibre spreads sweat thin; perforations vent for quick drying.
- Recycled inputs
- Both the Retransformed Polyester fabric and the Polygiene silver salt are recycled.
- Wash frequency
- Trunks stay fresh for multiple wears, reducing wash frequency and extending lifespan.
- Care instructions
- Preserve Polygiene by washing cold with mild detergent and low-heat drying.
Product record
- Title
- 3" Microfibre Athletic Trunk Retransformed Polyester
- Brand
- Le 31
- Price
- 20 CAD
- Availability
- In stock
Deep Research
How the Polygiene anti-odour treatment works
- Micro-perforated panels vent heat and moisture from the groin and glute areas, depriving odor-causing bacteria of the warmth and humidity they require to proliferate, while the Polygiene silver salt neutralizes any remaining microbial activity — a two-stage defence system that works better than either approach alone.
- Because the anti-odor treatment keeps the trunk smelling fresh, it can be worn multiple times between machine cycles — which not only saves water and energy but also reduces the fiber wear that causes athletic undergarments to thin and stretch prematurely.
- The active silver salt is derived from recycled silver, pairing with the trunk’s own recycled polyester construction to create a garment with both post-consumer fiber and a circular-materials antimicrobial agent.
- Polygiene’s treatment is designed to last the full life of the product, not wash out after a set number of cycles; as the fabric abrades with ordinary wear, newly exposed surfaces remain antimicrobial, so the trunk’s odor control persists for its entire usable lifespan.
- Polygiene Stays Fresh uses silver ions to inhibit odor-causing bacteria through three distinct pathways — disrupting cell walls, interfering with DNA replication, and blocking energy production — making the treatment robust rather than a single-point-of-failure surface coating.
How the micro-perforated panels increase airflow
- The micro-perforations are restricted to the sides and back — the zones richest in eccrine sweat glands — so ventilation is concentrated where thermal load peaks, while the front panel remains solid for a clean silhouette under shorts.
- During running or cycling, the stretch-and-recover motion of the hip and lower back flex zones repeatedly compresses the perforated fabric, forcing warm, humid air out and drawing cooler ambient air in, which amplifies the cooling effect beyond what static perforations would provide.
- The recycled polyester microfibre spreads sweat into a thin film that evaporates fast, but without airflow the vapour can become trapped; the perforations act as thousands of micro-vents that let this water vapour escape, keeping the fabric drier and less clingy than a solid-weave trunk.
- Polygiene's silver-salt technology neutralizes odour-causing bacteria on contact, and the micro-perforations deprive surviving bacteria of the moisture they need to multiply, creating a two-pronged freshness strategy that extends wear-time between washes.
Image Analysis
2 images- 01
Product
Front view of a male model wearing black boxer-style trunks with a flat black waistband and a small white numeric logo on the waistband; visible center front pouch and seam details, hemmed leg bands.
- Overall silhouetteMid-rise boxer trunk covering upper thighs with a straight horizontal waistband and fitted center-front pouch creating a contoured front silhouette.
1 region
x 0.09 · y 0.45 · w 0.82 · h 0.45 (high) - WaistbandFlat elastic waistband in black with a small white printed '37' followed by a degree symbol on the wearer's left front edge of the band.
1 region
x 0.54 · y 0.28 · w 0.32 · h 0.10 (high) - Waistband text“37°”
1 region
x 0.74 · y 0.31 · w 0.08 · h 0.06 (high) - Center front pouchShaped center-front pouch panel with visible vertical center seam and contour stitching that provides definition to the front panel; pouch material appears to have a slightly different surface texture than surrounding side panels.
1 region
x 0.36 · y 0.48 · w 0.28 · h 0.32 (high) - Vertical seamsVertical stitching seams run along the pouch edges and down between legs, visible as slightly raised stitch lines in matching black thread.
1 region
x 0.33 · y 0.50 · w 0.34 · h 0.40 (high) - Leg hem bandsDouble-layered hem bands at the leg openings create a folded cuff appearance with a subtle horizontal seam above the hem.
1 region
x 0.12 · y 0.78 · w 0.77 · h 0.12 (high) - Fabric finishSmooth matte black knit fabric on the trunks with a slightly different textured panel at the pouch center that appears microscopically perforated or patterned.Partial
1 region
x 0.34 · y 0.50 · w 0.28 · h 0.20 (medium)
Other
Studio shot showing a cropped male torso against a neutral gradient gray background; even soft lighting with mild shadows under the waist and inner thigh; image is centered and cropped above mid-chest and at mid-thigh.
- Background and lightingNeutral light gray seamless background with soft, even studio lighting producing minimal harsh shadows.
1 region
x 0.00 · y 0.00 · w 1.00 · h 1.00 (high) - Shot compositionFrontal crop showing the model from just above the nipples to mid-thigh, centered horizontally in the frame.
1 region
x 0.08 · y 0.06 · w 0.84 · h 0.88 (high) - Shadows and reflectionsSubtle shadowing under the waistband and inner thigh areas consistent with downward studio lighting; slight specular highlights on skin but not on fabric.
1 region
x 0.20 · y 0.40 · w 0.60 · h 0.50 (medium)
Colors
matte black· main body fabric#0C0E0Dblack· waistbandbright white· waistband logo- Overall silhouetteMid-rise boxer trunk covering upper thighs with a straight horizontal waistband and fitted center-front pouch creating a contoured front silhouette.
- 02
Product
Rear view of a male model wearing black athletic trunks with a textured, perforated rear panel, flat elastic waistband, visible center back seam, and short leg bands.
- View and fitRear full-seat view of low-rise trunks worn by a model; waistband sits at the natural waistline and trunks cover the upper thighs.
1 region
x 0.12 · y 0.38 · w 0.76 · h 0.54 (high) - Rear perforated seat panelLarge rear panel composed of a fine perforated or micro-mesh texture covering the seat area, with a rounded seam that follows the contour of the buttocks.
1 region
x 0.27 · y 0.52 · w 0.46 · h 0.30 (high) - WaistbandFlat elastic waistband in a solid darker black with a stitched center-back seam.
1 region
x 0.18 · y 0.44 · w 0.64 · h 0.06 (high) - Center back seamVertical seam runs down the center back from the waistband through the perforated panel to the crotch area.
1 region
x 0.49 · y 0.44 · w 0.02 · h 0.40 (high) - Leg bandsShort leg band cuffs finished with a folded hem that is slightly visible against the thigh edge.
1 region
x 0.20 · y 0.78 · w 0.60 · h 0.10 (high) - Side panel joinsSmooth side panels of solid fabric meet the perforated seat panel with visible curved stitching lines at the join.
2 regions
x 0.15 · y 0.54 · w 0.20 · h 0.30 (medium); x 0.65 · y 0.54 · w 0.20 · h 0.30 (medium)
Other
Studio shot showing the model from mid-back to upper thighs against a plain light gray background with even frontal lighting and soft shadows.
- Background and lightingUniform light gray seamless background with soft, even studio lighting producing mild shadows along the model's spine and under the waistband.
- Model presence and cropPhotograph includes a shirtless male model from shoulders down to mid-thigh; hands are relaxed at sides and the image is vertically centered on the trunk area.
1 region
x 0.05 · y 0.03 · w 0.90 · h 0.94 (high) - Image qualitySharp focus on garment details and skin texture; no visible text, labels, or props in the scene.
Colors
matte black· main fabric#0E1213textured black· rear perforated panel#2A2B2Ddeep black· waistband- View and fitRear full-seat view of low-rise trunks worn by a model; waistband sits at the natural waistline and trunks cover the upper thighs.
Documents & Data
Customer Reviews
4 total4 reviews · out of 5
So far so perfect
I’m very fussy about my underwear, as are a lot of men. Don’t let the thread-worn condition of our underwear fool you . It’s more of a fear of letting go until we’ve found a suitable replacement for our “lucky” underwear. It’s a personal choice of course,,but these tick the boxes for me. They are form fitting with 15% spandex, more than double what a lot of brands include. They maintain their support from the moment you put them on until you take them off. I’ve only worn them 2 times so far, so they’ve been washed 2 times. I wash everything before first wearing it. I followed the suggested wash instructions, however, I hang them to dry. Anything with a bit of stretch to it, lasts much longer if you don’t put them in the dryer. The heat will break down the stretchy fibers and over time it becomes shapeless and lumpy. So far these are the best underwear I have owned right out of the gate. Time will tell if they hold up and remain as such.
Confortable
Bon et pas cher!
Super confort
Bonne tenue, reste en place et bon support
Confortable
Confortable
Q&A
4 answered- What are the recommended washing and drying instructions to preserve the Polygiene anti-odour technology?
- To preserve Polygiene anti-odour technology, wash in cold water with a mild detergent, avoid bleach and fabric softeners, and tumble dry on low heat or air dry. High heat can damage the silver salt treatment.
- Does the microfibre fabric have a shiny or matte finish?
- The microfibre fabric has a matte finish. This is typical of recycled polyester microfibre used in athletic trunks, which prioritises a non-reflective look.
- How does the sizing of these trunks compare to standard US or Canadian sizes? Do they run true to size?
- These trunks run true to standard US/Canadian sizing. A size chart on the Simons website shows measurements: Small 28-30", Medium 31-33", Large 34-36", X-Large 37-39" (waist). Most customer reviews confirm they fit as expected.
- Are the micro-perforated panels visible through lightweight or thin pants?
- The micro-perforated panels are unlikely to be visible through most thin pants, as the holes are tiny and intended for ventilation rather than visual effect. They are located on sides and back, not front, so they typically remain hidden.