M130s spring for comfort of the user we enclosed a approximate reference (Since each marking is a world) for knowledge of the client:
1.1 Joule - 310 f.p.s.
2.M100 - 330 f.p.s.
3.M120 - 395 f.p.s.
4.M130 - 425 f.p.s
5.M140 - 457 f.p.s.
6.M150 - 490 f.p.s.
7.M160 - 526 f.p.s
8.M170 - 551 f.p.s