▪ Alumina insulation tube made by 99.3%-99.7% high purity alumina ▪ Alumina insulation tube max working temperature is 1700C ▪ The quality pass the SGS and DIN43724/DIN43725/DIN40680 ▪ Alumina insulation tube both end open with good verticalit ▪ Alumina insulation tube multi bores/holes can accept the custom.