Duct Clamp For Nominal Duct Diameter 20 in Product Type Duct Clamp Material Thickness 18 ga Material Stainless Steel Overall Length 20 in Inside Diameter 20 in Seal Material Nitrile Weight 1.92 lb Shape Round Standards Not Applicable Outside Diameter 20 in Material Grade 304 Compatible with Series QF Compatible with Brand Nordfab Series QF Maximum Temperature Rating 158 Degrees F