This extruded aluminum angle bracket is designed to work with 40 Series Metric Extrusion. These work great for additional bracing and using a Roll in T nut with a 16mm Buttom Head Cap would be an ideal way to attach this angle bracket to your extrusion.

Angle Bracket for 40mm Metric Extrusion installed on 40 Series Extrusion
(extrusion and fasteners not included)