Average face velocity = 390 fpm, based on filter capacity rating of 2 CFM per square inch of gross filter area. Free area averages 75% of grille core. For quick calculation free area (sq. in.) = listed width x height x .75

• Designed to fit a 20"W x 12"H hole; actual size is 22-5/8"W x 14-5/8"H x 1-5/8"D.
• All-steel construction; bright white finish.
• 1/3" spaced fins set at 20 degrees.
• Use standard 1" thick disposable filters (not included).
• Removable face for easy installation and cleaning.

Designed to fit a 20"W x 12"H hole; actual size is 22-5/8"W x 14-5/8"H x 1-5/8"D.Hart & Cooley