Years ago S&W had a replacement back strap that could be ordered from them. Easy to install and the grip feels like that of the 1911A1. I don't know if they are still available or not but maybe an email to S&W might get you the answer. It was never widely known and I would not have know about it if a factory rep hadn't informed me about it and sent me one to try. This was just after they came out with the 659 model and that was quite awhile ago.