39 sizes to meet your different needs There are 39 hole saw sizes available ranging from 16 mm to 200 mm. Choose from 7 piece sets covering 22 mm to 64 mm or 11 piece sets covering 19 mm to 64 mm. The effective cutting depth varies with diameter: for hole saws larger than 51 mm, the depth is 32 mm; for sizes 51 mm and smaller, the depth is 25 mm. material for reliable performance Speed Steel HSS Bimetal construction provides heat treated and rust proof performance. It offers heat resistance and wear resistance, delivering fast and clean cuts. The design combines speed steel teeth with rust protection and durability, making it suitable for repeat use in tough work. Efficient and clean cutting The hole saw teeth are sharp to reduce vibration for stable operation. Four chip evacuation holes enhance material removal, enabling quicker cutting and less clogging. The speed steel teeth edge adds shock resistance for dependable cuts. Useful tips for results When using the hole opener kit for extended periods, keep rotation speed under control with RPM at or below 1000 to prevent rapid wear. The surface is coated with a thin protective oil to guard against oxidation and rust; take care not to stain the tool and inspect its condition regularly. Practical use scenarios Installing electrical conduits or wiring holes in metal panels, cabinets, or control boxes in workshops or garages. Creating round openings in metal doors, housings, or sheet metal for mounting hardware or plumbing. Fabrication and renovation tasks that require clean, precise holes in aluminum or steel components, such as metal frames, brackets, or ductwork.