Insider’s undershirt was created as the solution for those who need to wear business and business casual attires in warm, tropical climates. With high temperatures throughout the year, the inconvenient sweat rings under the armpits are a frequent issue when wearing dress shirts. To prevent this issue, we created the undershirt, a garment specially designed to be worn in direct contact with the skin under dress shirts.

Our undershirt has anti-sweat action. It absorbs sweat and evaporates it quickly, before it can reach the outer layers. It keeps the dress shirt looking sharp and fresh for longer, keeping you ready for an emergency meeting at the end of the day and comfortable at all times.



How does it work?


The undershirt works with superior sweat absorption and antibacterial action that blocks unwelcome smells. It is highly breathable and allows a better control of body temperature.

Our inner shirt offers ultimate comfort, adjusting to the body without excessive compression while avoiding outlines and peeking necklines in the dress shirt and staying tucked in the pants. Its design - in addition to its elevated sweat control - will bring you the confidence of being free of sweat rings all day long without compromising style.


Sustainability: get to know our fabrics


Knowing that fashion is the second biggest polluting industry in the world, we combined all the technology of our undershirt with greener fabrics that hold CO2 control certificates.

That guarantees a traceable, closed cycle production with biodegradable rejects and the absence of genetically modified raw materials. Furthermore, our products hold the Oeko-Tex® label that certifies we don’t use harmful materials for human health.


Ethical, local labor


When Insider was founded, we discovered that the fashion industry is broadly known for its malpractices in labor and working conditions. We decided to manufacture our products in a local-sourced, ethically managed workforce based in the states of São Paulo and Minas Gerais, in Brazil. 

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