NOTE: Whatever size you wear in a Face Mask will also be the corresponding size to a Neck Gaiter

NOTE: The "EAR TO EAR - WITH FLEX" measurement will be the main guide to fitting a Neck Gaiter accurately

SIZE EAR TO EAR-RELAXED (not worn) EAR TO EAR - WITH FLEX (worn and pulled tight)
SM 11 to 11.5 inches 13.5 to 15 Inches
MD 12 to 12.5 inches 15.5 to 17 inches
LG 13.5 to 14 inches 17.5 to 18.5 Inches
XL 16 to 16.5 inches 19.5 to 21  inches