Sig Sauer P365 Extractor Spring. Wound from steel, this factory original extractor spring is a genuine Sig replacement component. Designed for Sig Sauer P365 pistol models chambered in 9mm, the spring provides tension to the extractor of the firearm to ensure proper movement when chambering rounds. The spring is crafted around the same relentless standards put into every pistol and rifle Sig makes. Kit up, dress up or replace your original parts with nothing but genuine parts from Sig Sauer.