1.Cut concealed pins in just 1 pass; these hole saws are perfect for jobs that require high performance and precision. Great for cutting wood, plastic, machined metal, nail wood, plywood, pipe and steel. 2.Stainless steel blades provide impact and scratch resistant teeth at high speeds. Steel at the soft spring creates a flexible material that allows the hole saw to absorb the impact of drilling through difficult-to-use materials. 3.Universal cutter that can be used in a variety of applications; great for plumbing, construction, aircraft, electrical, maintenance and automotive applications. 4. Faster, smoother cuts that don't vibrate like others; its variable pitch teeth; creates holes for 3-D plumbing installations, door lock installations, electrical conduit, pipes and antennas. 5.Scope of application: Iron plate, steel plate, stainless steel, aluminum plate, calcium silicate plate, plastic plate, resin plate, FRP plate