How to join t-slot profile with a Standard Nut and Bolt connection

How to use 3 way cubic connector for T slot Aluminium profile t slot connectors 3D INNOVATIONS T Slot 2020 Aluminum Profile L-Shape Interior Inside Corner Connector Joint Bracket 6mm for Aluminum Extrusion Profile tome of madness slot demo Description They are suitable for connecting, at any angle, aluminum T-slot framing profiles of 20 metric series Diameter of axle : 6mm

tuindeur met slot hornbach Buy 4Sets 20304045 Series L Type T Slot 90 Degree Interior Corner Connector Joint Bracket Fastener Aluminum Profile EU Standard at Aliexpress for