Constant comfort is the aim of our Tec-Wool Hat. We do that by using c_change„¢ technology which independently reacts to changing temperatures.    This is a great 3 seasons Hat! Our Tec-Wool Hat uses c_change„¢ by Schoeller® Switzerland technology membrane to ensure constant comfort. What is c_change® technology? Much like a pinecone, the c_change„¢ technology membrane opens when the outside temperature rises, and close again when the temperature drops. Look forward to: Constant comfort - c_change„¢ works to maintain an even temperature Keeping warm - discreet tuck away ear warmers can be pulled down in cool weather Staying dry - fabric repels both rain & snow Additional Features: Guaranteed for life Internal size adjustment device Hydrofil® sweatband to wick moisture away Keep valuables safe in the secret pocket Made in Canada Brim size: Front: 2 5/8"; Back: 2 3/4"; Sides: 2 1/8" Weight: 4.8 oz / 136 g Fabric: Black: 71% wool; 18% polyester; 12% polyurethane; Grey/black herringbone & Blue/black herringbone: 88% wool;12% polyurethane Care: Dry Clean Only  We say: Look at the sizing chart on the left to figure out your size and watch the video above.