Circulation D'air

A metallic vent installed on a wall with visible pipes
@tatsun_s_createT

TATSU

Hand using a cotton swab to clean the blades of a fan
pastap

pasta

Metal ventilation duct attached to a wall
take_apii1t

take_apii1

Metal ventilation duct mounted on a roof against a clear blue sky
ookinate23o

ookinate23

Image of an old cooling unit featuring a large circular fan grille
@kasako

かさこ