Slide-in T-nut loads from the profile ends. It is a strong, durable connection. An essential for working with slotted aluminum extrusion, these t-nuts slide into the side-slot of aluminum extrusion profile. Works with 8mm slot, 15 Series Series profiles. Compatible with 80/20 1515, 1530, Profiles. Slide in T-slot nuts are used to attach plates, brackets, and other parts to aluminum extrusions using matching bolts (not included).They are inserted into the end of the extrusion and create a strong connection. (Pack of 50) Item Dimensions (LxWxH) 0.700 x 0.630 x 0.250 inches