I found that there was a very noticeable difference between the etching of Philips tubular metal halide lamps produced in China and the etching of tubular metal halide lamps produced by Philips Belgium. And the date code and the detailed date exist at the same time. Does anyone know why?
(All images have been repaired)
picture 1:Philips HPI-T(normal)made in china
picture 2:Philips MH-T Color (Red) made in china
picture 3:Screenshot from the Belgian Philips 400W HPI-T Plus released by the user "FrontSideBus"
