Under armour coolswitch brassie stripe polo shirts newly available from under armours autumnwinter collection is the brassie stripe with coolswitch technology coolswitch is a technical design feature that allows heat to be drawn away from the torso keeping the wearer at a constant stable temperature and enabling premium comfortthe brassie stripe offers a upf rating of 30 and incorporates antibacterial properties into the fabric the antibacterial fabric has been designed to reduce odours an