Do not insert the drill hole cutter through the red positioning plate directly, as it is only used to mark the installation position of the hinge hole to locate the center. After marking, remove the positioning plate before drilling. The cutter fits into the plastic template hole. The hinge drill bit is made of premium carbide, offering high hardness, resistance to deformation, and anti-corrosion properties. The hinge drill guide is constructed from durable ABS plastic, making it sturdy and portable. The 35mm Forstner drill bit features a centered tip design for precise cutting. It includes a detachable depth-limiting stopper and clear measurement scale for easier and more efficient drilling. Note: The drill chuck should securely clamp the shank to prevent bit drift. Hole diameter of the red positioning plate: 35mm / 1.4 inches. The hinge drill guide helps quickly mark accurate hidden hinge holes. The "V"-shaped locator aligns with a center reference line to precisely position drill points, preventing hole misalignment. Simplifies and improves accuracy in cabinet door installation. This concealed hinge drilling kit is ideal for use on wood, plywood, and veneer. Suitable for cabinetry, furniture assembly, hinge mounting, and various DIY projects. User-friendly for beginners, enabling quick identification of hinge and mounting plate centers. Material: Plastic + Alloy Color: As shown Package Contents: 1 set x 35mm Forstner bit (3 Pieces) Note: Light reflection and differences in display screens may cause slight variations between the color shown in the image and the actual product. Measurement may vary by ±1-3cm.