Our Ultimate 45 ACP 1911 Extractor is the only extractor that is made from the correct spring steel called out by the military print. I have had every extractor that I could purchase tested to determine the steel alloy. All of the extractors that I had tested were made from the same incorrect steel. The Ultimate extractor has the correct nose shape and the proper radii for the most reliable function. The Ultimate extractor will maintain its tension long after the others have failed. Tensioning instructions are included with every Ultimate Extractor. Every Ultimate Extractor is Rockwell tested to insure correct heat treatment. The Ultimate Extractor is not only heat treated it is Austempered for maximum wear resistance.