Cuts insulated flexible round duct and also cuts the duct liner's wire rib coil. Compound leverage provide smooth scissors cutting action and a big 4 3/8" cutting length makes the job go even faster. Pointed bottom blade easily punctures through outer skin, insulation and liner of duct to start the cut. A heavy duty wire cutter is located away from scissors blades. Thumb operated latch ensures that sharpened blade edges stay closed when not in use.