Connecting 20 Series extrusions at a corner can be done in a few different ways – this strong corner brace being perfect in many cases. This can be used by itself, or in conjunction with other types of connection (end tap and drill, corner connector kits, side plates, etc) to create an even stronger and more ridged frame. The kit includes the corner brace, two drop in M5 nuts, and two M5 socket cap screws with captive washers. The corner brace is made of aluminum and features tabs to help align it with the aluminum extrusion; the included hardware is SUS304 stainless steel.  Slot the nuts in and tighten the screws and this will provide a much stronger corner in your assembly.