25 Pack 2020 Series M5 T Slot Nuts Roll-in Spring Ball Loaded Elastic Nuts Compatible With 2020 Series Aluminum 2020 M5 T Slot Nuts for 2020 aluminum extrusion with 6mm slot, use for T-slot aluminum profile 20x20 series.Spring ball loaded makes these T slot nuts sit and stay where you want them,and don't slide around while your trying to screw into them.It was so much easier than fiddling with the stock T nuts that refuse to lock in place correctly.You can insert and remove these T slot nuts easily.If you work with T slot extrusions,these are a must have.These T slot nuts fits perfect on 2020 extrusion or 2020 rail with lots of different components on your rail.For you to mount something else.If you also lost pieces to your printer and need replacement, they fit nice and secure in rails.Use them to add new brackets to stiffen the frame on your 3D printer (Tevo Tarantula).All high quality carbon steel construction,high hardness.Nickel-plated surface, rust resistance.2020 Series Aluminum Profile T-Nuts widely Use to build CNC routers, 3D printers, CNC cutters, CNC plasma cutters, robotics projects, 3D carvers, machine guards, workstations,and more.Easy to be roll into T slot of aluminum profile.colour:SilverMaterial:aluminumsize:12*8*6mmPackage Contents:25*2020 Series NutsOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.