Aluminum is a good material. Durable and workable. And it is likely what the trigger group is made of. Super glue will hold it, but it does crazy bad things to plastic so be careful. Use a sharpie pen (black) to make the shiny go away.
The trigger housing is polymer.
NRA Certified Pistol Instructor & RSO, IDPA Sharpshooter, Project Appleseed Rifleman
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