The Osram L58W/840 T8 Fluorescent Tube is an 5 Foot 58w T8 Tube in colour 840 - cool white. Colour 840 is the latest colour reference, the older L58w tubes may say 640, 33 or 740 on the tube itself. This is the latest version and replaces all. Colour temperature is still 4000k cool white. The improved design keeps it\'s true colour for longer and has an increased average life of 15,000 hours + For full technical specification see Data Sheet and select wattage/colour combo. Osram Part Number: 4050300517957