4" 3 Hour Vertical Mount Fire Door 2661-20X18 Residential Registers & Grilles To adjust diffuser

To adjust diffuser

3/16" cross bars

Aluminum 3 cone T-Bar diffuser with a fixed face

REVIT FILES Egg Crate T-Bar Filter Grille 2" with Round Collar

4" 3 Hour Vertical Mount Fire Door 2661-20X18 Residential Registers & Grilles To adjust diffuserh3. Standard Features * 2661 Square or rectangular fire door for vertical mount only. Maximum dimension 60x60. For damper free area chart A click here * 2663 Out of Airstream fire door. Square or rectangular for vertical mount only. Maximum dimension 60w x 52h. For damper free area chart B click here * 2665 Round fire door for vertical mount only. Available 4" thru 52" round. * 3 hour rated * UL and California State Fire Marshall approved * 4 1 4"