The thermal shirtFRONTIER 2 isdesignedtobe wornunderneath eachjacketwithpurposes of insulationandto managethebody temperature.Thefront panelofWindBarrier®REV'IT!helps to keepthe body dryand warm,while the closureof the highcollarwas placedon the side,helping to preventbulkinessunderthe zippersof theouter jacketandkeep the windout.