... controlled well, high precision, good quality.Product:quartz sleeve, opaque quartz tube,milky quartz/ large milky quartz tube,opaque quartz tube,milky quartz ... The product is widely used: halogen lamps, mercury lamps, single-ended lamp, automobile lamp, stage lamp, thermocouple, copiers lights ... and low OH, etc. They’re the best heat resisting material for lamps like: halogen lamps, mercury lamps ...