Material:HSS 4241(Suit for use in hardness under 25 degree artifacts,The plate thickness under 5 mm) Type: 4-32mm:4,6,8,10,12,14,16,18,20,22,24,26,28,30,32mm 4-20mm(4,6,8,10,12,14,16,18,20mm) 4-12mm(4,6,8,10,12mm) Length: 4-12mm length: About 6cm 4-20mm length: About 7.2cm 4-32mm length: About 9.7cm