Excellent performance: fast easily drill a hole with enlarged top part, which allows a screw/bolt fitting into it, lying below the surface. Good function: counterbore hole, effectively reduces the risk of panel's splitting, makes every screw nail/bolt appear flush with the furnitures surface, nice. Various countersink dill bits: the set contains different size bits, enough, satisfied for multiple demands. Wide application: it works with electric hand drill or bench drill, very suitable for drilling on wood, plastic, etc. Total Two Combinations for Option 5pcs: 2.8*8mm, 3*8mm, 3.2*8mm, 3.5*8mm, 4*8mm 6pcs: 2.8*8mm, 3*8mm, 3.2*8mm, 2.8*10mm, 3*10mm, 3.2*10mm Specification: Material: Alloy #43; Carbon Steel Color: Orange Silver Type: 5pcs / 6pcs (Optional) Package Size: 5pcs: 90*90*18mm / 3.54*3.54*0.70in 6pcs: 108*90*18mm / 4.25*3.54*0.70in Package Weight: 5pcs: 160g / 5.64oz 6pcs: 200g / 7.05oz Note: Countersink drill bit set only, other accessories in the pictures are not included. Due to lighting or other reasons, the picture and material object may slightly differ. Due to manual measurement, there may be deviation, please in kind prevail. Packing List: 5 * Countersink Drill Bit