Shape of Ceramic Tubing is square, have two side open, exclusive use in Plasma Corona Electrode, Spark Machine and Coating machine. The specifications of square alumina ceramic tube can be customized according to your needs.Product details:1.Material: 95% 99% alumina ceramic.2.Resist high temperature:1600℃ to 1800℃.3.Can be customed tubes’ size and tube: yes.