What does the check mark at the rear panel label of the E3600 series bench power supply mean?

The check mark on the rear panel label shows the AC power rating for this unit which shipped from the factory. User must ensure the correct voltage is used to power on the unit.

User is responsible to remove and replace any tag or label showing the previous rating with their own latest installed rating if they subject it to any modification that cause the power rating to be different from originally shipped from factory.