The characteristic feature of this cut lies in the fact that the drill holes are arranged in zigzag. In this way a larger opening is obtained because the drill holes can break out between the preceding rows. Each vertical row of holes breaks out a layer. If the front holes do not break out to the full depth, the burnt-out holes indicate the direction of break for the following row of holes since the holes are arranged in zigzag. The name, triangle cut, is due to the distribution of the holes at the working face and the form of the initial opening.