1.Material:AL2O3 85%-99.5% 2.inside diameter= 0.3-2mm ,Outside diameter=1.0-8mm ,lenght=100-2200mm 1.Material:AL2O3 85%-99.5%2.inside diameter = 0.3-2mm ,Outside diameter=1.0-8mm ,lenght=100-2200mm 3.Feature :Great mechanical strength ,good resistance to thermal impact ,good insulation and highfrequency characteristics under high temperature ,breakdown volage and volume resistance and ...