Used Materials: Leather, Aluminum How to Use: Upon arrival, the shoulder strap is straight. When using it, gently bend it over your thigh to adjust it to the shape of your shoulder. Actual Usage Experience: It puts absolutely no strain on the neck and is very comfortable to use. Also, the length of the strap can be easily adjusted, and the hook part has a safety structure, so there's no worry about dropping your precious instrument. I felt that this was undoubtedly the best product among the straps I've used so far. Although it takes a little effort to adjust the shoulder strap to fit you at first, it's very comfortable to use once adjusted. Highly recommended product.