Our custom machined Linear Rail Mounting Bar (for 7H size linear rail) saves you the trouble of messing around with the tiny M2 nut adapter. Our T nut is made with stamped steel and zinc plated (early versions have a blued finish instead) for corrosion resistance. Simply slide the T nut into your extrusion and fasten the linear rail with M2 machine screws as you normally would.
We also called it Tnut Bar.