High Capacity magazines are restricted in some areas, so please read carefully. This listing is for ONE  Magazine. Smith & Wesson’s 4000 series full sized pistols had two magazine well widths, .815 inch and .818 inch. Here are quality extended capacity magazines for the ones with .818 inch wide wells. They will not fit the .815 width pistols. They will fit all the 4013 double stacked pistols, no problem. These  are magazines to fit Beretta 96 series pistols with only an added magazine release slot for the Smith & Wesson 4000 series pistols, including models 410, 411, 4003, 4004, 4006, 4026, 4043, 4044, 4046, and any TSW variants of those pistols.  Manufacturer is Pietro Beretta of Gardone, Italy. Construction is folded steel body, with piano tensile wire springs, steel inner plate, and high impact polymer cartridge follower and floorplate. Finish is factory Brunitron coated steel with full length tig welded smooth milled backs. Each magazine holds 11 rounds of .40 S&W ammunition. Note that we have added a correct width spacer to mate the Smith & Wesson’s grip frame butt. Our local machinists have added a magazine release slot to engage Smith & Wesson magazine catches for their 4000 series pistols, but only the ones set up on right handed shooter. They will Not lock the slide open on the Smith & Wessons on the last shot, so operators will need to be able to count to Eleven. These magazines will still fit all variants of the Beretta 96 pistols. Surface detractions are moderate, with moderate amounts of carry wear and finish freckling. We rate them as Very Good Condition. Magazine bodies have not been modified or altered beyond the catch slot addition.                No CA CT DC HI MA NJ NY OR RI or WA Civilians.