A HALF ZIP THAT PASSES THE COMMANDO TEST In WWI, wool was so important to British soldiers on the front lines that knitting wool sweaters was seen as a patriotic duty. By WWII, wool&&';;s reputation was further solidified. However, SAS members spent extended periods in the field, laden with rucksacks and additional equipment, constantly on the move. After witnessing repeated failures with their traditional wool sweaters, the SAS sought a lighter alternative, reinforcing the shoulders for durability. This became the iconic British Commando Sweater, and the inspiration for what we call the "commando test" - to pass muster, Merino wool must be reinforced in high stress areas. If it&&';;s not, it simply fails too fast like the traditional wool garments that the SAS rejected. We build ALL GORUCK Merino Wool tops with reinforced paneling on the shoulders so your Merino shirt keeps its structure better over the long haul - representing the standard for performance in the Merino wool category and passing the Commando Test. This ensures that your Merino shirt maintains its shape over time, while still providing all the advantages of Merino, such as odor resistance and perfect temperature regulation, regardless of the adventure or mission at hand.