JBF National conical ejector pins(countersunk head ejector pins) are manufactured using the highest quality certified H-13 die steel. These pins have a 45 R/C core hardness, 68/74 R/C surface hardness, carry a g6 tolerance, and are laser inspected throughout the entire manufacturing process. Due to their smaller head when compared to typical cylindrical head ejector pins, conical pins are great for applications with head dimension issues. Please see component diagram below.