It's magpul. - Magpul Industries M-LOK QD Sling Mount

As the manufacturer that makes the most common aftermarket parts for firearms ( good thing ), they are reasonably priced and worth the price. This quick Detachment sling mount should be the go to at local firearms stores. They do include a liquid nylon agent on the screws to help lock-in after tightening down but can be a hassle to actually tighten down pass the agent.