Polar Bear Shop Heko Onbu This item allows you to use a Heko obi (a type of Japanese soft fabric belt) for back carrying, similar to an onbu strap. (It is not an onbu strap itself.) I bought this because I struggled to back carry with a Heko obi when my older child was young. It's in relatively good condition with little use, but it's black so dust is noticeable, and the head support is missing. *This is used with a Heko obi (see photos 5 and 6). Since the head support is missing, it's difficult to use with younger babies. Please be careful not to purchase this by mistake, thinking it's an onbu strap. Please understand the above before purchasing.