This track features former Soundgarden and Audioslave vocalist Chris Cornell. Slash told Musicradar.com
: "Chris was great. Promise was probably the most unorthodox piece of music that I'd written, it was very different. It was one of those things, I don't know why I thought of him for that song more than any of the others, but I sent it to him and within 48 hours he sent me this great lyric and we were off and running. it was as simple as that. Everybody seems to like this one."