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Kalenji Seamless Running Boxers, Men's
1-piece boxers (seamless) for maximal comfort and support. Ventilated areas for enhanced breathability.
Free shipping over $49
Final Sale: No returns or exchanges
Free returns
Free pickup
San Francisco, 735 Market St. Options
Select an available color and size to see options.
Product Features

Moisture wicking
Fabric absorbs, diffuses, and dries quickly. Ventilated areas at the groin
Irritation reduction
The use of seamless technology reduces chafing.
Questions & Answers
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Product Customer Reviews

I've loved these for years! It's such a shame that they haven't been in stock for such a long time! The seams in others always cause me painful chafing, but these have allowed me to run pain free! Please bring these back!
Very confusing sizing. On ask the items
Please get XXL sizes. I normallly wear L but even the XL of which I got of these is tight. Great for sport/active, but otherwise a larger(XXL) size would be perfect. The most seam free truck I've ever found( i've looked). They only have a small half-seam across the perineum. Would buy more of these if there was a larger size.
I love these. I have so much trouble with underwear for running and these are brilliant. I had to go one size up, normally M and got an L, and they fot perfectly.
Hi Adam
Thank you for your review and we are glad to hear that you are delighted with the product! We take feedbacks and reviews into consideration as we strive to make better products for all sports users out there! This product has ventilated areas to ensure breathability and comfort for users.
Feel free to view our website for more products or drop by to our nearest Decathlon store to you to check out more sports products catered for sports users!
Muhammad
Omni-Channel Sports Advisor
Decathlon Singapore
I've loved everything I purchased from Decathlon, especially the running gear so I gave these a shot. They are super tight on the legs, the band folds over and there isn't really any frontal support.
Great fit and very comfortable on runs.
Great fit, comfy , really good fit easy to wear when running in leggins or working out in the gym.
Sizing was perfect, comfortability outstanding
If 32 - 34 waist get extra large.
I have purchased underwear from decathlon in the past and had no problem with sizing. This product is grossly under sized. I would estimate you would have to go up 3 sizes to get them to fit. I would say the underwear looks a good quality, but I would not be able pass judgement on comfort, as would not of been able to get them.
Would recommend- well-fitting and comfy
I read the reviews and saw the comments about the seam, which is small and where the legs come together. However, this has caused me no problems and I have bought a second pair. The boxers have stopped my chafing, provide good support where required and feel good on the legs (I have tree trunk legs from my rugby playing days). Plenty of stretch and support.
I am a fairly serious runner. Wore these once. Nearly ruined me. Never been in so much pain in my life. Truly unbelievable. Very very dissatisfied with this product. Pls consider carefully prior to purchase.
There is a totally unfinished seam in a very critical point in the crotch. Wearing inside out partly solves the issue, but the legs then roll up and causes other chafing. I love Decathlon, but this product is a fail.
Hello Rob,
Thank you for your review of our Kalenji Running Boxer. I'm sorry the boxer is not suitable for use. I have noticed that we have received a small number of reviews relating to the position of the assembly seam. The team will continue to monitor this situation. I propose that you return the model purchased, at your convenience - https://www.decathlon.co.uk/decathlon-return-policy.html
Robert
Excellent product.... bought a trial pair in Spain, now bought more because I’m impressed! As good as, and much better value than, the expensive branded ones I’ve been buying. Highly recommended!
Size Guide

Additional Product Information
Composition
Main fabric
- 14% Spandex
- 43% Polyamide
- 43% Polyester cationic
Waistband
- 22% Spandex
- 78% Polyester cationic
Origin
Imported
Product testing
These boxers have been tested in the lab and in use in the field by athletes of all levels. They were chosen by all our testers for their capacity to provide comfort during running in warm weather. Flat seams prevent chafing.
Superior quality. Unbeatable prices.
For 40 years, Decathlon has delivered the best value in the retail sports industry by offering high-quality, sustainable and cost-effective products.
Decathlon makes the difference
-
Research and development
delivers high-quality cost-effective products
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State-of-the-art production processes
minimize manufacturing costs
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Optimized supply chain
reduces retail prices
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Minimal retail footprint
lowers overhead and indirect costs

Kalenji Seamless Running Boxers, Men's
Your location: City, ST
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Heavy products return policy
If you return a product you will receive a refund for the purchase price plus any applicable sales taxes, less any non-refundable charges.
Decathlon will cover all shipping costs associated with your return except for items excluded from our return policy such as bikes, basketball hoops, snowboards, surfboards, tents, and other larger / heavier items.
Return costs for heavy products:
Weight Thresholds | Shipping within California | Shipping outside of California |
---|---|---|
> 9 lbs | $20.00 | $25.00 |
> 30 lbs | $50.00 | $65.00 |
> 100 lbs | $100.00 | $125.00 |
> 200 lbs | $200.00 | $230.00 |
If you return a product at any of our store locations, we will gladly help you find the best alternative product or refund you on the spot.
