It is a replacement part of the main plastic part of Manfrotto Compact Light tripod.
Mine got broken when was trying to tighten the main pole. This is a full replacement part. to assemble you will need:

• 3 x M3x16mm screw
• 3 x M3 nut/self-locking nut

With some modifications, you can use original nuts but I didn't like the idea of screwing them directly into the plastic.

I am attaching raw files from DesignSpark Mechanical