The strap fasteners don't hold up under the weight of a sub. We'll be replacing them with a stainless steel product. Everything else (mounting hardware on the railing) is top-notch.
The assembly on the stanchion is good and solid. However, the first time it was used, a locking tab jumped out and was sunk in the sea. A solid metal tab as a tensioner would be better here!
As read in previous comments, the Strap is made of plastic and NOT SUITABLE for traction. It breaks immediately and, as happened to other buyers, ends up in the sea. I advise against the purchase because you will be forced to change the belt with another one in steel and the cost is not worth it.