This is an osram 4ft 21w substitube basic led t8 tube with a g13 cap these lamps have an average life of 40 000 hours a lumen output of 2000 lumens colour 830 or 2100 lumens colour 840 or 865 and an a class energy rating these replacement led tubes will work on old style magnetic control gear without bypassing the ballast but the ballast must be bypassed when using in high frequency fittings the tubes are not dimmable and have a 150 degree beam angle