The Particle Size Magnifier (PSM) is a mixing type Condensation Particle Counter developed and manufactured by Airmodus Oy. Using diethylene glycol (DEG) as working fluid, it can activate particles as small as ~1 nm, while a butanol-based CPC is used to further grow the particles above the optical detection limit. When the PSM is operated in scanning mode, it also gives size information of particles between 1 and 3 nm. Thus the PSM can directly detect even the smallest newly formed particles, and can be used to study the very first steps of particle formation and growth.