These printable parts are part of a soldering fume absorber / extractor. There is a post about this build here.
Warning: This isn't an easy print!
The shell pieces can take over 5-8 hours (each) on a Prusa i3 MK2 and mostly fill up the bed (an i3 MK2's is 250 x 210 x 200 mm); (lengthy side of the large pieces: 201 mm, wide side: 160 mm). Please be sure that you're committed before pressing print.
Prints requiring support: filter - cover.stl (the slot for the cartridge has an overhang when printed face down). The case filter - case.stl works best with support if possible, but you can also go without (like I did, on accident).
That said, general settings work well: 0.2mm layer height and a decent amount of filament of your choice.