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SPRiT  MX  Progressive Springs     


-  World Premier 99% precision Oct  2018 

-  Challenging to 99.5% Supreme Precision - avrg 0.3g variance  

-  Made in Korea of super-precision premium materials under SPRiT control



I have designed  Progressive rate springs to be much lighter than the conventional springs by 8g - 10g until the actuation point as Graph 1.   

The force rises rapidly after actuation, results in the same bottom out weight as the linear springs.  If you want to experience bouncier bottom out, please try one or two level heavier springs. 

Progressive springs are hard to find any practical example in the electronics industry, the production is trickier and takes much longer time.


* No Polarity on Progressive springs.

  According to the Newtonians,   Fab  =  - Fba  


  You can say this simply,  "When you press the lighter end, the heavier end will be pressed by exactly the same pressure. vise versa."    or 

   "It damn doesn't matter, which end.  You feel the pressure exactly by the pressure you press."


Please Enjoy Your Premier Builds 




Bottom out Force    


55 P     -  Starts at 23g, actuates similar to 45 S.  Oct 2018


63.5 P  -  Starts at 25g, actuates similar to 55 S.  Oct 2018 


68 P     -  Starts at 28g, actuates similar to 58 S.  Oct 2018   


72 P     -  Starts at 30g, actuates similar to 63.5 S. Oct 2018

78 P     -  Starts at 33g, actuates similar to 68 S.  Oct 2018


100 P   -  Starts at 36g, actuates similar to 78 S.  Jan 2019  


125 P   -  Starts at 38g, actuates similar to 85 S.  Jan 2019  



For further info  > 


Progressive 99.5%


    Free Return if items have serious production defects.  Free Refund before the item has shipped out. 


    FedEx  or  EMS Express 

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