... length is 1199mm For exampleZW13D12Y-H164 stands for:UV germicidal lamp,13W,single-ended,OD 12mm,ozone produceW,ozone freeZ,tube ... length is 164MMFor exampleZW55D17Y-H533 stands for:UV germicidal lamp,13W,single-endedD,OD 17MM,ozone produceYozone freeW,tube ... length is 553MMFor exampleZW95D15Y-Z1550 stands for:UV germicidal lamp, ...