See measurements in images and compare them to your best fitting garment to get sizing. *** Older merino wool baselayer shirt from an innovative company I/O Biocompatibles. Hard to find items, no longer being made. 1/4 zip, extremely fine and lightweight. Unique camo print. Tags are not legible, approximate size: M, please use measurements! *** Reach out with any questions. Thanks for popping in! Pre-owned item with signs of use/wear. Heavy use, multiple holes, fraying by collar. Discoloration on collar and throughout - latter from probably washing together with darker items. Have been laundered with appropriate wool detergent. ***