My Kimber TLE II has it (came that way from the factory) on the front strap. My understanding is that the work itself is an extra $100, so if I had to send a gun back for it, I wouldn't. It does however, feel "right." Now, all three of my Para-Ordnances have 20 lpi on the mainspring housings. I don't like this one bit. Extended shooting sessions at the range result in a sore palm where the MSH contacts. Yeah, I could wear gloves and recently aquired a pair of shooting gloves.