The X-LARGE size mask is good for big and tall adults. When folded in half, the X-LARGE measures 5.5" tall x 5" wide.
The LARGE size mask is good for most adults and teenagers. It what the two adults and one teenager in our house wear. When folded in half, the LARGE measures 5" tall x 4.5" wide.
The MEDIUM size mask would work well on children and petite adults. When folded in half, the MEDIUM measures 4.5" tall x 4.25" wide.
The SMALL size mask would work well on small children. When folded in half, the SMALL measures 4.25" tall x 4" wide.
To determine your size, measure from your ear to ear, around on the jawline, and divide that measurement in two, that will give you the maximum size width you should wear. For example, my ear to ear measurement is 9", so 4.5" would be my "max" width. The LARGE is 4.5" wide, and just fits me ear to ear. I could also downsize to the MEDIUM and wear it with a little room between my ears the ends of the mask. I could not fit the X-LARGE, because that is 5" wide and the ends would overlap my ears.
To purchase a mask, see photos below for fabrics available and ordering instructions.
From Left to Right: X-Large, Large, Medium, Small