Better performance, for long time use. They can be directly into the aluminum slot hole in any of the assembly post. nut can be simply and securely fixed on the aluminum profile, it can be automatically positioned and locked. T-Nuts suitable for aluminum profile, widely used for building industrial aluminum frame structures and robotics projects. Features - Color: Silver. - Material: Carbon steel. - Size: 1.00 x 1.00 x 0.40cm/ 0.39 x 0.39 x 0.16 inch. - High hardness, you can insert and remove these T slot nuts easily. If with T slot extrusions, these are a must have. - These T slot nuts on extrusion or 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. - These T slot nuts where you want them, and don't slide around while your trying to screw into them. Package list: nuts