General description This adjustable self-centering drill guide set is designed for woodworking and carpentry, made from industrial-grade 6150 aluminum alloy, ensuring strength and high corrosion resistance for durability and a long service life. It features a large tripping range of up to 60mm and includes 9 drill bushings in three sizes to accommodate various drilling needs. Technical specifications Material: Aluminum alloy Color: Blue Drill bushing sizes: 6mm, 8mm, 10mm (3 pieces of each type) Suitable wood size: 17-60mm / 0.67-2.36 inches Dimensions: 23.5 x 10 x 3.8 cm / 9.25 x 3.94 x 1.50 inches Usage Adjust the positioning scale to set the distance from the first hole to the end of the card. After fixing the position, select the appropriate drill bit that matches the drill bushings to begin drilling. Remove the nuts from the scale after drilling three holes. Use the locating pin to secure the hole on the third hole, ensuring equal distance between each hole. Drill all holes