Replaced 2 original percussion locks with L&R RPL locks. The first a Hatfield, main spring broke, no luck finding a spring. Since L&R makes a Hatfield Flint replacement, called them and they said they could make a Percussion lock, no problem. A bit more deeping of the lock cavity and it fit and worked very well. I was so pleased with the lock speed and reliability, I ordered and installed one in my Renegade. Good people to do business with!