It all started when two friends invented a powerful air cleaner in response to the COVID-19 pandemic.

Dr Richard Corsi and Jim Rosenthal created an air cleaner with phenomenal performance and low cost, and then gave it away to the community as an open source, DIY project that anyone could build from local parts. 

This approach made the Corsi-Rosenthal box an immediate hit. It has become widely used in schools in the US, winning awards and attracting the attention of the White House, where, we are pleased to say, you will find Corsi-Rosenthal boxes in use.