This 7-piece set is ideal for preparing electrical installations and for drilling in soft and medium-hard wood, insulation boards, drywall, plastic, or metal. It includes 6 bi-metal hole saws with diameters of 40, 54, 65, 68, 74, and 86 mm, a mandrel with a 5/8" thread, and a center drill (Ø 6 mm) made of high-performance high-speed steel. This allows you to achieve precise holes with a cutting depth of 55 mm. The specially alloyed tool body with HSS teeth ensures high durability and smooth operation. The hexagonal shank (Ø 11 mm) allows for quick locking of the hole saws in the chuck of your drill or cordless screwdriver. The set comes in a high-quality 2-component plastic box, allowing you to transport the parts safely and store them neatly. The hole saws are TÜV certified, ensuring that you are choosing safe quality products.