i’m interested in getting a zimi mask, but unsure of which size and model to get. it seems like the small and medium are the same height but different widths, but i don’t know what to measure for that. i feel like my head/face is on the larger size but i have a very flat profile and nose. kn95s with an ear saver band have been most comfortable for me but they tend to be slightly too tall for my short nose. can anyone talk about their personal experience with sizing for zimi masks?

other questions 1. how long does shipping from PPEO to the northeastern US take? 2. which model should i get?

edit: 3. anyone have experience with the valved filters?