Fine Pima cotton. I bought these to wear at home and they are a very good t shirt. I haven't washed them yet so I'm still waiting to see if they shrink but I hope they don't because they are just as good as they are. I'm slim, 76kg, 6ft 2in and the medium length is fine (assuming they don't shrink in the wash). A small downside is that I've had several 'regular' versions of this shirt before and the inner label (the one on the bottom left of the inside) was soft material with perforations that could easily be torn. without irritating friction on the skin. These skinny versions don't have that - they just have the standard glossy polyester label which is permanently sewn on and can irritate you by rubbing the sides.
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