Resp-o-Rator filter adapter

For people with beards, most respirator masks simply don't work. There's only one popular low-cost, beard-friendly respirator on the market, the Duxerity Resp-O-Rator. Unfortunately, they use a proprietary filter size, requiring you to order filters directly from them. As far as I can tell, their filter is a HEPA N95, but there's not a lot of documentation. If you want N100 or an oily particle tolerant filter, you're going to have to buy a much larger and more expensive face mask.

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