Before use, you should wash the glass and wipe it dry. The glass must be clean and dry or else the diodes will glow constantly. It is recommended to use a paper coaster. If the beverage is cold, Luminarus might collect condensate which will cause the diodes to light up.

Bright-glow useful life is at least 300 hours (more than three years with 15 minutes every day). After this, the diodes will still glow, only less brightly. And the very glasses are always good to use.

Handle carefully:
— use water no hotter than 65 ºС to wash (dishwasher safe);
— do not use in a microwave oven, induction or other furnaces;
— do not hit or put pressure on the bottom;
— do not drop, hit or shake the glass;
— store at 0 to 35 ºС above zero.

The battery may temporarily fail due to exceedingly high or low temperature. At temperatures below zero it works much worse, and enduring irregular conditions may result in shorter useful life.