This is the Printable .obj for the V4 F2 HEPA Filter Respirator. This version was designed to exhaust CO2, and water vapor buildup from the mask to make it more comfortable to wear, as well as provide less constant air resistance for the user. As you can see in V4 an intake valve was made for the interior portion of the filter, as well as a release valve for exhaust. My intent for this mask is not to be used in medical settings other than for emergency use only. This is a prototype and  has not been clinically tested. 3D Prints are known to be porous as well as have other issues which may prevent them for clinical use.   

ATTN: YOU MUST PRINT VALVES AND GASKET IN TPU.

Other Versions and base molds are located on my website, JoshHughes.Studio/Shop and are free to download as well. 

The filter which attaches to this mask can be found here. https://www.amazon.com/3M-Filtrete-Devil-Vacuum-Filter/dp/B001AO2RTM

The Filter must be a 3M Filtrete “Dirt Devil* F2 Type Part # 6580B (HEPA). 

The filter that fits this mask is a 3M F2 Dirt Devil HEPA Filter which is certified to filter particulate down to .3 micron. This is the same filtering requirements for the N95, P95, and R95 masks recommended for use to protect people from viruses such as COVID-19. Though I have faith that this design will work I do not claim any guarantees for the protective ability of the mask, and use of this mask is at own risk. Lastly I am an artist, who freelances doing industrial design I do not claim to be an expect in the field of medical equipment.