The body features 260gm merino wool fabric with a touch of lycra174 for stretch and a deep front zip for easy heat dumping in the underarm panels icebreaker have used lightweight 180gm eyelet merino mesh that actively controls temperature during high output pursuits while in the higher wear areas around the elbows and forearms they39ve added 230gm merino and polyester waffle jersey for added abrasion resistance flatlock seams throughout eliminate chafing during fast paced days why ice