【New Upgrade】The dent rods are made of hard and thick spring steel hardness is greatly enhanced, not easy to be Bent or break. 【Multi-Functional Stainless Steel Pen Heads】7pcs stainless steel pen heads with M8 screw is universal for dent rod and Repair Pen,that is equivalent to 14 kinds of concave and convex repair functions,this set is enough to repair the dent of the whole car.