Used this to replace the weak flimsy spring that came with the neogeo x controller, controlling the joystick is a lot more fluent now.
LS-55 Nice Stiffness
Posted by Manny D. on 28th Jun 2016
I currently use the LS-55 spring for my Sanwa JLF, It has a nice medium stiffness to it compared to the light stock JLF spring. I also have a LS-33 spring which is even lighter than the stock JLF spring. Both of these springs can be combined with the stock JLF spring, combine the LS-55 for a heavy spring or combine the LS-33 for medium stiffness similar to the LS-55.