Product material: brass pure copperSpot specifications are: 2mm, 3.17mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm and other specificationsHexagonal aspect size is 7mm,The diagonal distance is 13.6mm,The opposite facet to the alternative side is 12mm,The total peak of the coupling is 18mm,The cylinder top is 12mm,The outer diameter of the cylindrical part is 11.5mm,There are 2, 3.17, 3, 4, 5, 6, 7, 8, and 8 styles of inside diameters of the cylindrical part.Suitable for connecting shafts with diameters of 2, 3.17, 3, 4, 5, 6, 7, 8, and eight diameters respectively,The screws for aspect fastening are M4 screws, and the solving screws for the middle hole of the hexagonal floor are all M4 screws.