Specifications of red quartz tubes: 1.high purity, good spectral transmission, 2.well controlled dimension and lower OH High Quality Dark Red Quartz Tube We can supply different type and sizes of color quartz tube for heating elements,like ruby quartz tube, black quartz tube, gray quartz tube, yellow quartz tube and etc.,OD10mm,12mm, 16mm, 18mm and etc., Dark Red Quartz Glass Tube