T Nut - Series 30 and 60 - clean joint aluminium slot profile
T Nut Stainless Steel Material Slot 8mm M4 M5 M6 Nuts for 30 Series Aluminum Profiles - China T Nuts, T Slot | Made-in-China.com
Amazon.com: Odinest T Nuts Tee Sliding Slot Nuts 40 Series M8 Threaded Slide in Pre-Assembly for 40x40 Aluminum Extrusions Frame with Profile 4040 Sereis 8mm Slot for CNC Router Build Rail 3D