The PSA Custom Premium AR Replacement Inconel AR Takedown Pin Spring replaces the factory takedown and pivot detent pin springs in your AR platform rifle or pistol with Inconel 600 nickel-chromium alloy springs. The alloy used in these springs is designed to withstand much higher temperatures than normal springs which results in a much longer lifespan. Made in America with PSA's 100% Full Lifetime Warranty. Features: High Strength - impervious to aging or stress corrosion Hot & Cold workability- Greater heat resistance than normal springs. Resistant to corrosion