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900 B-Fast, Swimming Trunks, Men’s

Sale price: $10.00 Regular price: $19.99

Men's trunk-style swimwear, designed using the best fabric to ensure excellent chlorine-resistance and optimal comfort.

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Size: Select a size
Size Guide

This product runs small

Sale price: $10.00 Regular price: $19.99

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Free shipping over $35

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San Francisco, 735 Market St. Options

Select an available color and size to see options.

Model: 8648322

Product Features

A photo of the 900 B-Fast, Swimming Trunks, Men’s in use

900 B-Fast, Swimming Trunks, Men’s | Our design teams have developed these briefs for the swimmer looking for a classic shape and who needs support.

Men's trunk-style swimwear, designed using the best fabric to ensure excellent chlorine-resistance and optimal comfort.

Chlorine resistant

more than 200 hours of use: recommended for regular use.


Swim trunks provide good support


Easy to adjust around waist using drawstring and a special silicon toggle.

Product Customer Reviews

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99 Reviews
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900 B-Fast, Swimming Trunks, Men’s
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Just right for swimming

Perfect tight fit, fabric in good quality. Comfortable to wear in water

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The product is good, just that the size chart and actual product do not match

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Running n Swimming

It's great for both running and swimming

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Покриха очакванията ми и това което търсих

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Мисията на Декатлон ще остане непроменена - да правим спорта достъпен за възможно най-много хора, по един отговорен към природата начин.

Благодарим Ви, че оценихте нашия продукт!

Спортни поздрави,

Екипът на Декатлон България


Sedí dobře,jen odolnost se prověří sama časem. Byl jsem jen jednou na bazénu.

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Moje úplně první zkušenost se slipovými plavkami a jsou skvělé. Skvele se v nich plave. Pevně drží obsah plavek, což je mi příjemné. Jen se špatně šňůrka rozvazuje, když se zamotá, protože je tenoučká.

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Falsche Grössen

Ich hatte zwei unterschiedliche Badehosen zur Abholung in der Filiale bestellt, Grösse L bzw. XL laut Decathlon Grössentabelle (gemäss Taillenumfang). Geliefert wurden die Grössen M bzw. M-L. Rücknahme und Erstattung in der Filiale erfolgten anstandslos. Die eine Badehose (Nabaiji 900) war in der Filiale in der passenden Grösse jedoch vorrätig. Qualität, Möglichkeit der Filialabholung, Umtauschmöglichkeit, Hilfsbereitschaft des Personals etc. alles einwandfrei. Aber der Versand einer falschen Grösse und dies gleich doppelt, sollte nicht möglich sein. Dafür ein Stern Abzug.

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Schnitt gefiel nicht, ansonsten gut.

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creo que deberían poner aunque sea tres XXXL

hoy en día la gente estamos mas gorditos, y los bañadores XXL es poco, ay que poner tallas grandes, un saludo

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Ideal para natación

Bañador ideal para la práctica de la natación

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Will buy another pair!

Great fit, very comfortable. I have used all the other brands but the design and fit of this suit is the best yet!! 🏊‍♂️

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Muy buen tejido

Tejido muy comodo y comfortable.

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Bañador calidad precio

Muy buena relación calidad precio para la práctica diaria de la natación,aguanta muy bien el cloro ,muy contenta

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Disfrutar en la piscina.

Totalmente adaptable y cómodo, buena calidad precio.

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Size Guide

Size Guide Visual

Additional Product Information


Main fabric

  • 22% Elastolefin
  • 78% Polyester cationic


  • 100% Polyamide


Swimming trunks – side height 3.1" Swimwear should prioritize comfort. It should enable you to move with ease. That is why it is important to choose the shape of your swimwear carefully. The swimming trunks have a classic and timeless cut, providing great freedom of movement, as well as plenty of support. Details are positioned so that they mold to your body shape.


22%- Elastolefin 78% - Polyester Our engineers have developed a polyester-based fabric and replaced the spandex fibers with fibers that give it sufficient elasticity to ensure user comfort while protecting it against the damaging effects of chlorine. This thread also offers the following benefits: - quick drying. - only loses 3 to 4% resistance throughout its lifespan. - UV-resistance: Colors are more stable.

Aquaresist technology

Products bearing the AQUARESIST label are guaranteed to deliver chlorine-resistance throughout their lifespan. They will keep their elasticity and be resistant to light. For these reasons, they are recommended for regular or intensive pool use.

Determining the environmental impact of our products

The environmental impact of the product is calculated over its entire lifecycle using different indicators. An ABCDE score is provided to enable easy identification of the most environmentally-friendly products when comparing products of the same type (T-shirts, pants, backpacks). Decathlon chose to apply this voluntary environmental labeling system. Web: Video:



Product testing

Products labeled with AQUARESIST certification are tested under repeated cyclical loading in a pool of chlorinated water for more than 200 hours. No deterioration of elastic strength was observed throughout the test. Unlike a standard swimming product, the product remains intact.

Storage instructions

Store the swim shorts in a dry place.



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
  1. product-research

    Research and development

    delivers high-quality cost-effective products

  2. State-of-the-art production processes

    minimize manufacturing costs

  3. Optimized supply chain

    reduces retail prices

  4. laptop-checkout

    Minimal retail footprint

    lowers overhead and indirect costs


Size Guide Visual