30-300mm Adjustable Black Circle Hole Saw Drill Bit Set DIY Woodworking Tool Features: 1.  Sharp and durable carbide tip can be reused after grinding. 2.  The hole diameter can be adjusted by the distance from the drill bit tip to the center. 3.  Alloy steel with heat treatment can be used for thin-film plate. 4.  Can be installed and operated on the electric drill and bench drill. 5.  Widely used in wooden board, plastic board, gypsum board, etc.   Specifications: Material: alloy steel Color: black Shape: airplane Hole diameter range: 30-300mm / 1.18-11.81in Weight: Approx. 534g   Package Includes: 1 x Adjustable Hole Saw Drill Bit Set   Note: 1. Before starting operation, check if all the screws are tightened. 2. Be sure to hold it during operation to prevent accidents. 3. When replacing the drill, it is necessary to cut off the power. 4. Cuttings generated during drilling should be cleaned by special tools rather than hand. 5.Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.