50pcs/lot Aluminum Profile T Sliding Nuts, Slide T Slot Nut with Clear Box for Aluminum Profile Accessories(European Standard 20-M4) : Amazon.ca: Tools & Home Improvement
Slide nut with long spring | OBO
Amazon.com: uxcell Slide in T-Nut, M8 Half Round Roll in Sliding Threaded for 4040 Series Aluminum Extrusions Profile, Pack of 15 : Industrial & Scientific
Smith Brothers Stores Ltd | M10 CORE Channel Slide Nut (No Spring)