This 140mm magazine fits Staccato 2011 & Double-Stack 1911 handguns. These Atlas Gunworks Classic Double-Stack 1911 magazines come in a 20-round configuration. Atlas Gunworks recommends classic magazines to shooters looking for a tough magazine that feeds awesome and locks back reliably in most modular 1911 double stack pistols. Features: Caliber: 9mm Capacity: 20 Rounds Tube: 140mm Stainless Steel Follower: Lockback Spring: +18% Basepad: Aluminum, Prevents Over-Insertion Classic Magazines Compability- All Atlas Gunworks Pistols with a tactical or carry magwell All known Staccato 2011 style and 1911 double stack modular pistols with no magwell or a Staccato Compatible Magwell Staccato*: Staccato C2, Staccato P, Staccato XL, Staccato XC using a Staccato Magwell Springfield: Prodigy 5" 1911 DS, Prodigy 4.24" 1911 DS *Some Staccato Pistols made after August of 2024 have new frame dimensions, which prevent the use of all known aftermarket magazines.