How to measure your face to see if this mask fit you.
If you look in the description there is a face seal size. You would need to measure the width and height of your face. Width is from one (outer) corner of the eye to the order corner and the height is from the eyebrow to under the nose.
Ideal for medium faces - face seal size W4 3/8 * H3 1/4 Crystal, liquid silicone injected skirt and strap Double edge comfort seal Ultra low volume Swivel and adjustable buckles Broad peripheral view Tempered glass
Optical lenses available from -1.0 to -10.0 by increments of 0.5 (for near sighted)
Optical lenses available from +1.0 to +4.0 by increments of 0.5 (for far sighted)
Bifocal lenses available from +1.0 to +4.0 by increments of 0.5 (gauge reader)