Alt v2 should be considered viable. 3d printed PPE mask that fits 2.125" cuts of approved filter materials, elongating a precious resource. Simple design, easy to print, vacuum form or mold. Accelerated print times and material optimizations for higher production rates. Observed 24 mins to print single, 28.5 grams, uses 2.125 filter, heat formable and cut for individual safety fit seal. $0.60 material cost. get +30 from a k spool. Filter cap wings for noggin connection as suits you best. Cap made to fit within mask footprint for nesting if positioned so. I have printed single and double perimeters in TPU and am very happy with results. Lets keep people safe! Iterate and critical feedback VERY welcomed!