It is a small leather strap. I think that it is smaller than seen in the image.
Thin purple. Length: about 4.92 inches, Weight: about 0.005 pounds.
The top of the leather has become a hook.
The following is Japan of the Amazon store.Made in Japan.　Designed by Kisaragi.
http://www.amazon.co.jp/gp/aag/main?ie=UTF8&asin=&isAmazonFulfilled=1&isCBA=&marketplaceID=A1VC38T7YXB528&orderID=&protocol=current&seller=A243IZHCXRV5V9&sshmPath=

Technical Details

Product Details

Package Dimensions
Width : 1.26 inch
Height : 0.47 inch
Length : 3.15 inch

Shipping Weight: 0.16 ounce (View shipping rates and policies)

ASIN : B00GBMY6I8