Blast Gate, For Nominal Duct Diameter 4 in, Body Material Grade Type 1, Body Material PVC, Overall Length 5 in, Product Type Manual Blast Gate, Blade Material PVC, Maximum Temperature Rating 140 Degrees F, Seal Material Not Applicable, Standards Cell Class 12454, ASTM D1784, Inside Diameter 4 1/2 in, Color Gray, Air Inlet Size 4 1/2 in