Shape and Size. Tapered, single hole, 6.5mm inner diameter for the hole, 21.5mm diameter in the base. 22mm overall length. Made of high grade Al2O3 Alumina Ceramic, which ensures a great mechanical strength and stable performance while working. Resistance on high temperature. Capable of the temp up to 1600 degree in celsius(2912 fahrenheit) 1000V Insulatsion, high corrosion resistance, scratch proof and Good chemical stability. Application. Mainly used in electric heating elements, protection sheaths, insulators. 6mm Inner diameter single bore aluminia Aluminous porcelain ceramic tube.Materials: Alumina Oxide Ceramics (Al2O3)Size: 6mm diameter hole, 22mm overall lengthCap Size: 15.5mm in heightBase Size: 11mm overall height(6mm height in first step, 5mm in second step)Shape: Tapered (Separate Cap and Base)Voltage insulation: 1000VMaximum temperature resistance: 1600 degree in Celsius/2912 degree in fahrenheitWeight: 23gApplication: electrical heating wires, insulators, high temp protectionPackage Content:1 pcs 6mm Inner Dia. Aluminia Ceramic Tapered Insulator