Sunstar Kadomaru Pro-NEO Black Corner Cutter 1 カウント

This corner punch can handle 3-5 sheets of paper of weight under 64g/m2, and allows you to choose among small sizes (3mm), medium sizes (5mm) and large sizes (8mm) of corner radiuses. This Pro Neo model requires half of the force to use compared to the original corner cutter. The punch also features a lock at the end of the devise so that the lever won't move when it's idle.