Brand: ZAMST Product Name: Shoulder Wrap (Shoulder Supporter) Retail Price: ¥8690 Size: M (Arm circumference at the base of the arm: 34-41cm) I purchased this item, but the size didn't fit when I tried it on, so I haven't used it. The outer box has a tear at the opening. Please understand that this is a used item that has been opened, although it was only tried on. Regarding the size, the arm circumference at the base of the arm (the circumference passing through the shoulder protrusion and under the armpit) should be 34-41cm with the arm relaxed. Thank you.