What does “Power Saving Function” mean? Sandra Salvatore June 19, 2018 03:49 Updated Follow With 10% power or less, lights will automatically switch to lowest lumen output. Related articles What is COB? What is Lumen? What does “Memory Function” mean? I have the Street F135/R14. What does the F and R mean? What are the Terms and Conditions for the ATPO? Comments 0 comments Please sign in to leave a comment.