Replacement Filters-10 sets of 4

For decades employees have been complaining about cold air blowing on them from overhead air diffusers. The Filtered Air Diffuser will eliminate the draft while improving indoor air quality.
Features:

10 sets of 4 filters each.
* 4 way adjustable flow patterns.
* 4 Filtered air vents.
* Made of durable steel.
* Change filteres approx 4-6 months.
* Preventsdust build up on ceiling tiles.