Instructions:1. When using the thin plate hole opener, first insert the front end of the drill and the cutter into the round hole of the hole opener, connect the cutter to the electric drill and lock it, then put the three branches on the shelf, the stigma screw Tightly, to prevent the hole opener from sliding; insert the left and right positioning pins upward into the small square hole of the shelf, and finally adjust and tighten the tight screw according to the size of the arc to be cut. Fix firmly to ensure the accuracy of cutting round holes.2. standard circular arc cutting, should use core plate, in order to protect the circular arc edge smooth and beautiful, should also be on the job to drill a 3 mm the positioning of the eye, and 12 mm drill a hole, insert bit manhole for inside and outside round cutting.Weight: 0.5kg 25*15*6cm.Fix the double-head cutting machine to the ordinary electric drill. The pneumatic tool or the drill can make any cutting on the metal plate, and the cutting will be straight and the cutting of the round attachment will be more precise.