Need a Sportstyle or gym cap that can handle the heat? Put on the Under Armour Men's Spacer Mesh Training Cap. Thanks to its UA Threadborne Microthread construction, it offers a stretchy, breathable feel with ventilated spacer mesh panels to keep you cool. It has the UA Classic Fit with a pre-curved visor a low profile. To figure out your fitted hat size, measure the circumference of your head where your hat will rest. Size M/L 56-58 cm. Size L/XL 59-62 cm.