The Honeywell North 7700 respirator, shown with P100 cartridges. Size medium pictured.

The Honeywell North 7700 Series is a half face elastomeric respirator produced by Honeywell.

The Honeywell North 7700 comes in 3 sizes (S, M, L).

Like most elastomeric respirators, the Honeywell North 7700 feature a one-way exhalation valve. While the US CDC considers exhalation valves on N95s to be acceptable for source control (as of April, 2021; see NIOSH study as well as this presentation on elastomeric respirators - 19:15, 40:00 marks), some may choose to cover the exhalation valve of the respirator with e.g. a surgical mask.

A list of "DIY" exhalation valve filters (not vetted!), some from 3D printing websites:

See also