Trying to cut thin sheet metal with your jigsaw? You need the right blade, and this Bosch T 118 G 5-pack is it. These blades are specifically designed for cutting very thin metal plate, in the range of 0.5mm to 1.5mm thick (that's like 20 to 16 gauge steel). They have a 'wavy set' tooth design that's milled (not ground), which helps make cleaner cuts in metal and reduces vibration. Bosch is a powerhouse in power tool accessories with over a century of experience, so you know you're getting a quality product. The pack comes with five blades, which is great because jigsaw blades for metal can wear out or break. Just pop one into your jigsaw (they fit most standard models) and you'll get much better results on ductwork, flashing, or thin aluminum compared to a standard wood-cutting blade.