Replaceable Print Head for LX900 Color Label Printer. Regular replacement of the print head will be necessary approximately every 10,000 prints*. To ensure uninterrupted printing capability, purchase a backup print head. *This is not a guarantee of print head life. There are many variables that could extend or shorten the life of the print head.Replaceable Print Head for LX900 Color Label Printer. Regular replacement of the print head will be necessary approximately every 10,000 prints*. To ensure uninterrupted printing capability, purchase a backup print head. *This is not a guarantee of print head life. There are many variables that could extend or shorten the life of the print head.