I recommend the product but only because it's the only one that is on the market that fits and ar 15 - FAB Defense MG-9 Foregrip And Magazine Carrier For Double Stack 9mm

The problem is it is a friction locking device and there is no release button to press to release the mag. That means if you need a mag you are going to have to pull the mag real hard to get it out of the device. Or, adjust the friction where it's loose enough to get the mag released but then the mag is going to fall out of the device when you are running. I still use it and have purchased 3 of them for my AR's in 9 mm but I don't like it. As soon as somebody makes one with a locking release button I will purchase 5 -10 of them and sale these 3 in the yearly garage sale. It's better than nothing and I love everything else about the device.