Good question... Don't know. I do know that the LVL 1 Support Rep I spoke with told me that MK25's springs were not coated in anything special (and he put me on hold to check).
Can you be more specific... Did their spring kit lower the DA & SA trigger pull significantly? I took this from their site:
"Suitable for range-only and competition pistols, the kit reduces DA and SA pull weights and stacking in both modes to the maximum degree possible in factory-stock actions consistent with reliable operation."
Gunsmith Name: RBARTON

Comment