HEPA Filter designed for use with an 80mm fan.
this design uses the standard roomba 800/900 hepa filters (which are cheap to buy) and provides ducting to an 80mm fan.
also includes electronics housing.
and a version with a cut out for a pwm controller (such as Noctua NA-FC1 4-Pin PWM Fan Controller )
only the HEPA Cartridge/box needs supports when printing.
printed in petg at .2 layer height YMMV