This is a throw lever for a DBAL A3 IR laser and Illuminator. I highly recommend doing the illuminator spacer mod before using this to get the full benefit of it. I don't know if everyone's A3 has the illuminator positioned in the exact same way, but I recommend fully widening it and then (looking at it from the front) position the throw lever at the 5 oclock (or closest) bump. That way the throw lever should hit the post and stop right before it gets too small to be useful. I also included a version without a stop so you can focus it as much as you want.
I printed it in PETG, takes about 13mins and it's a good press fit.