dp speed master recoil fjeder til tm hi capaDynamic Precision have mad a new kind of Recoil Spring in 2 different editions. This one is the "Speed Master" which is designed not to give the wildest recoil, but to give a better control when shooting. These Recoil Springs are made of spring steel. The Non Linear spring design with a special calculated number of coils gives a more precise control on the recoil speed and better tuning for different slides. There are 2 springs in the package.