This 80/20 T nut measures .203 x .386 x .630 inches long with a 1/4-20 thread and comes with a ball spring. For use with 1010, 1020, 2020, and any other 1.0" based aluminum extrusions. Made out of 1045 steel with a bright zinc finish. The ball spring allows you to hang this t slot aluminum extrusion accessory in a vertical position. This t-nut works with 1/4-20 bolts (not included) to attach joining plates, corner brackets, hinges, and other t track accessories to 80/20 aluminum extrusion. This high quality and sturdy 1/4 20 nut will make a great addition to your fasteners hardware toolbox. Perfect for any home improvement enthusiast or general DIY'er. This t-nut can be used in a wide variety of applications including 3d printers, cnc machine, building industrial aluminum frame structures, CNC laser cutters, Robotics Projects and more. The roll-in T-nut with ball spring is a fastening option that loads from the profile ends or side, which is helpful for applications where the ends are inaccessible. The ball spring holds the T-nut in the T-slot, even when the profile is in a vertical position, simplifying the assembly process.