M size ring to keep finger joints causing pain, such as Heberden's nodes and Bouchard's nodes, at rest. This is a general medical device. - Brand: HeberLoop - Size: M (38-48mm) - Purpose: Health accessory I purchased this on Rakuten, but I am selling it because it did not fit my finger. I have widened it to adjust the size, so please understand that this is a used item before purchasing.