... 20mm-650mm 4.Outer diameter: 20mm-340m Specifications1. Main applications: Used in electric vacuum device and light source parts, etc. ... mainly export to Korea, Japan and Germany.5. The main market: North America, South America, eastern Europe, southeast ... pipe, silk, target materials, boat and crucible, etc.Main applications: Used in electric boosting glass kiln electrode, playing molybdenum rod, ...