... ozone produce, ozone free, tube length is 1199mm For exampleZW13D12Y-H164 stands for:UV germicidal lamp,13W,single-ended,OD 12mm,ozone ... is 553MMFor exampleZW95D15Y-Z1550 stands for:UV germicidal lamp,95W,single-endedD,OD 15MM,ozone produceYozone freeW,tube length is ... 1550MMFor exampleZW95D19Y-Z1554 stands for:UV germicidal lamp,150W,single-endedD,OD 19MM,ozone produceYozone freeW,tube length is ...