Efficient All-in-One Tool: This set combines pre-drilling, countersinking, and depth control into a single operation, eliminating the need for multiple tool changes. Ideal for countersunk screws (3-12 mm diameter), it can save up to 70% of your working time on installations and renovations, significantly reducing the chance of errors. Consistent Precision: Featuring an integrated metal stop ring, our drill bits ensure uniform depth with each use, preventing over-drilling and producing clean, burr-free countersinks. This feature makes it easy to achieve professional results, even for beginners, ensuring that screw heads sit flush and invisible. Superior Durability with HSS-M2 Steel: Constructed from high-quality material for hardness between 62-64 HRC, our drill bits offer exceptional heat and wear resistance. They outlast standard countersinks by up to 300%, allowing for precise drilling in hardwood, MDF, and wood composites over extended periods. Universal Compatibility: Equipped with a 1/4 inch (4.0 mm) industry-standard hex shank, these drill bits fit all cordless drill drivers featuring a bit holder. This design ensures non-slip power transmission even under high torque, preventing the bits from tilting during use. Comprehensive Professional Kit: This set includes four precision-calibrated countersinks (diameters 2.8, 3.2, 3.5, and 4.0 mm), covering 95% of all wood screws. A durable storage block is included to protect the cutting edges and organize the bits, making it an essential tool for flawless furniture assemblies. Packaging Details: 1 * Stop limit countersink drill 4 * Drill Bits (2.8 x 8 mm, 3.2 x 8 mm, 3.5 x 10 mm, 4 x 10 mm) 1 * Small Wrench Color: As Shown Material: Metal Package Contents: 6-Piece * Countersink Wood Drill Bit with Depth Stop