The Tracksmith Harrier is my go-to running shirt. Merino is a fantastic performance fabric. However, I realized that I need to size up to get the sleeve length I prefer, which means this XS long-sleeve Harrier in crimson heather needs a new home. Shirt is in very good pre-owned condition. Merino 89%/nylon 11%. Approximate flat measurements (see photos): Pit to pit: 15.25” Arm length: 23.5” Length: 24” Smoke-free and pet-free home. All reasonable offers considered.