... , 16-25V 4.OEM supply 5.Customize Industrial corundum tube /ceramic tubeHigh temperature furnace Al2O3 alumina tubesSpecifications1.95-99. ... Model 2. Graduation mark 3. Installation forms 4. Protecting tube diameter and materials 5. Precision grades 6. Using temperature 7 ... For example:Armoured thermocouple,K Type,I level,Fixed thread,Protection tube GH3030,length 450mm,Insert depth300mm, WRNK-231,K,L ...