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Diamond Theory Clothing

Notorious: Mass

Notorious: Mass

Regular price £90.00 GBP
Regular price Sale price £90.00 GBP
Sale Sold out
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  • Notorious Mass Fit
  • Windsor Collar 
  • Long Sleeve


We challenge you to find a better fitting shirt.

We have designed the perfect cut to accommodate real Mass. What does that mean? It means this shirt will fit broad shoulders, a big back and a wide core.


We use a blend of 97% cotton and 3% elastane.

Why? Simply put, because this is the best fabric to use. Cotton is lightweight and breathable, which means you are comfortable and don’t overheat. We use a small amount of elastane to allow for a little bit of stretch to aid comfort. We don’t use too much so the fabric remains lightweight, breathable and top quality.

The Shape

The shape comes from the Diamond Theory cut. There is no other shirt on the planet that is cut like this. This is the Diamond Theory cut that was developed over 3 years. This is designed specifically for athletes with real Muscle and Mass.

The End Product

All this added together means that you look like money, the quality fabric, the Diamond Theory fit put together with an athlete’s physique means you look awesome.

Before you order

Before you order make sure you measure yourself and choose your size according to the size guide. Take your chest measurement and your waist measurement. We’ve done all the leg work, but we need you to make sure you choose the correct size.

Athletes only!

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