Round Die- Made of alloy tool steel, hardness and wear-resistance.Application- Round dies are suitable for general purpose threading. Can process, correct or clean the external threads. Ideal for maintenance and repair work.Features- Conical locking hole, strong locking and not loose. Perfect for re-threading existing threads in hard materials like metal and making new threads in soft material such as plastic.Easy To Use- The positioning groove of the die should be aligned with the fastening screw in the middle of the die wrench, and the screw should be inserted into the slot of the die and tightened.Tips- It needs to be reversed every 1/4~1/2 turn to facilitate the chip discharge from the chip hole. Suitable lubricating oil should be added to the cutting edge of the die when tapping the thread.