Notch Classic Fitted Hat Red Blank was designed to specifically meet the needs for a practical hat for firearms instructors as well as a hat for range instructors. This red range hat will work perfectly with your eye protection and/or sunglasses and help keep them perfectly in place! We also increased comfort by replacing the top button with a 1" x 1" velcro square! Features include:Patented Notch technologyWorks with virtually any style of glasses (SEE THE PERFECT FIT GUIDE)Breathable A-Flex stretch fit fabricStylish structured low profile fitPremium moisture wicking sweatbandWhich notch location do you need? CLICK HEREWe offer our patented notches in two locations: Standard Notch and Terra Notch (named after our co-founder).The Standard Notch (pictured above) is designed to work with most wrap-around or sport style sunglasses, shooting glasses, and safety glasses. These styles have a curved appearance, designed to conform to the contour of the head.The Terra Notch is designed to work with most aviator or fashion style sunglasses as well as prescription eyewear. These styles are more squared off at the corners, causing the frame to sit further away from the face. Available sizes: XS/Y, S/M, L/XL, XL/XXL Hat Sizing: To determine your Notch stretch-fitted hat size, measure the circumference of your head where the sweatband of your hat will sit. If you don't have a tape measure, you can also use a string and measure it against a ruler. Find your measurement on the size chart to determine your hat size. Stretch-fitted hats may vary slightly within the same size category. When in doubt, order the next size down. Notch Fitted Hat Size Chart