Face Mask with valves

Based on https://www.thingiverse.com/thing:4228729

But I added two valves, for inhale and exhale.
The valve can be made of thin polyethylene or, better, rubber by screwing them onto a small screw.

To fit the edges of the valves more tightly, heat a flat surface, such as a ruler, and melt them into a perfect plane.

 The edges of the mask can be made less sharp and rubbed if you put insulation on them on a round cable, like molding. It must be cut lengthwise and the wires removed.

As filters it is better to use HEPA fabric. It can be taken from the filters for a vacuum cleaner. Three layers are quite easy to breathe.

I also lengthened the mask a bit so that it was not so crowded.

Но я добавил два клапана, на вдох и на выдох.
Клапана можно сделать из тонкого полиэтилена или, лучше, резины, прикрутив их на маленький шуруп.

Чтобы края клапанов прилегали плотнее нагрейте плоскую поверхность, например линейку, и проплавьте их в идеальную плоскость.

Края маски мож