Material of the UVC photon emitter: Quartz glass UVCDiameter: 18mm Length: 100mm Wavelength: 253.7nm The product has passed the quality test by the National Electronic Light Source Center for Quality Supervision and Test. By proper use, it will not cause light radiation demage by excessive exposure. For the safety, quartz is used for the glass. The advantages are: high light transmission rate, better thermal performance, low coefficient of thermal expansion and high insulating property. Contact: Shirley Email: xt4@