NeoMag
Magnetic in-the-pocket mag carrier that holds a spare on two neodymium magnets and disappears like a pocket-knife clip.
The NeoMag is the deepest-concealment way to carry a spare. Instead of a holster, a small machined back plate clips inside your pocket and two high-strength neodymium magnets grab the floorplate end of the magazine. From outside the pocket all anyone sees is a titanium clip that reads as a folding-knife clip. The magazine draws straight up and out, and the cant-adjustable clip lets you angle it to match how the pocket sits.
The Gen 2 rebuilds the original around a 6061 aluminum back plate (hard-coat anodized) with a black-Cerakoted titanium clip, and the two-magnet stack roughly doubles the retention of the first generation. It comes sized Small (.380), Medium (9mm/.40), and Large (.45/10mm) so the magnet seats on the right amount of steel. This is the pick when no waistband real estate is available and the spare has to ride in a pocket without a visible holster.
Add the NeoMag Gen 2 to your build and see how it enhances your platform.