These pneumatic shears run on compressed air and contain few moving parts, so they typically run cool, have a long lifespan, and weigh less than corded or cordless models. Single-cut shears use a pair of blades that cut like scissors to maneuver along curves with greater ease than double-cut shears. They cut flat sheets and navigate ridges to cut corrugated metal. Double-cut shears drive their pivoting center blade through two fixed, outer blades to remove thin strips from materials. They make long, straight cuts on flat material without bending or curling its edges.