Predrill with 10mm. Dimension plug M10x50mm. You can use a screw with a diameter of 6 to 8mm. Predrill with 6mm. Size of plug M6x30mm. You can use a screw with a diameter of 4 to 5mm. pre-drill with 8mm. Dimension plug M8x40mm. You can use a screw with a diameter of 4.5 to 6mm.