Great but not for me - Black Scorpion Outdoor Gear Universal Magnetic Magazine Carrier

I recently bought a handful of these thinking they were adjustable since the picture OP has shows the mounts as adjustable; they are not. They’re still a great holder for your mags if your belt is 1.5”. The magnet is really strong so if you don’t want your mag slamming into the mount I would recommend to place a thin rubber pad to cushion the impact. I would recommend these with a inner/outer belt as well since just having a single belt might result in the mounts shifting.