Ventilation collection:
https://3dsky.org/collection/shared/5333943 

CORONA + VRAY (2013)
FBX CORONA + VRAY (2009)

A set of ventilation grilles for embedding and embedding in the ceiling, walls and floor.
The grilles are available in several sizes and colors. Some models can be edited using Edit Poly to fit any required size.
The links to the models are in the attached text file.

The set contains :

- Ventilation grilles with perforations of 920 x 250 ,700 x 300 mm.
- Linear diffusers, length 200, 500, 600, 900, 1000 mm.
- Square grilles with a grid of 250 x 250, 300 x 300 mm.
- Linear slit diffusers LSD x 1, 2 and 3 slits.
length 665, 1955 mm.
- Corner ventilation grate 630 x 360 mm.
- Slotted ventilation frame, 500 mm long.
- Round diffusers with a diameter of 61, 100, 130 mm.
- The diffuser is a designer round..
- Corner grilles height 280, 150 mm.
- The corner grid is 500 x 500 mm.

Other sets :
https://3dsky.org/users/solomon5555/models