A gusset enables freedom of movement flatlock seams reduce chaffing during high activity and a brushed waistband feels great under layers and merino39s natural odour prevention means that you really can wear them day after day on your next adventure why icebreaker merino the merino is an ancient breed of alpine sheep over millions of years they evolved a superfine highly breathable fleece to protect them from freezing winters and scorching summers it will do the same for you what is