M150 Spring - MADBULL

After 6 months try and error, we finally made the most "colorful" spring which is more beautiful than anyone else.
The color is not painted. It is hard-coated by special process.
Calculated carefully by computer and test by 100000 times punching.
Our spring has been proofed that the length and force are still consistent. We just want to proof that our spring is not just a "spring". It is a MadBull spring and it is "colorful."