ISMI Magazine Spring for STI 2011/Infinity High Capacity

Wound with high tensile, chrome silicon wire that’s shot peened, heat treated, then stress-relieved for the longest service life possible, without cracking or failure.
Fits STI/Infinity standard magazine, all calibers, up to and including 140mm +1 and +2 round base pads. Important when using 200 gr. bullets and heavier, 11 coils.