This is a hood support clip that the end of the hood support can clip into so it doesn't rattle. There is one in the center of the hood for the middle of the hood support. This one is for the end. It snaps into a hole that already exists in the inside of the hood, so you're not doing any damage to the car. It is also easily removed, just pinch it at the base and lift it out.
<a href="https://www.atomicfilament.com">Atomic Filament</a> PETG
Don't print this in PLA, use PETG. I printed it first in PLA and it becomes loose after the car sits in the hot summer sun. PETG has a higher melting temp. I printed again in PETG and the problem was resolved.
To print with PETG, the hotend temp should be 235-245C. At 250C the plastic starts to out-gas and you'll see tiny bubbles in your plastic. It is a thicker plastic so you should slow your print speed down by 1/3-1/2, unless you have a geared double-hobbed pulley extruder like the BondTech BMG extruder.
The bed temperature should be 70-75C.