I called them today and the lady told me the best thing to do is give them the FP spring measurements and they will match it up in theri database to see if they have a stronger one to replace the one in my M9. I borrowed a snap-on caliper and got the measurements in the thosandths like they want it. I want to know if anyone here already went that route. If available, I gonna order a few and if anyone wants to try, I will sell them at cost. We will at least save some shipping.