In full the tag reads: Heavy. Assisted lift may be required. Bend your knees."
As I handed it to be x-rayed another passenger saw me looking at the tag. He said its a just a reminder for the passenger to lift at the knees when living a bag even one that meets the weight limits. He added it's probably because someone tried to blamed the airline that he hurt his back for lifting his own bag which he backed. I just wondered: could that be true? In this world of blame, it just may be.