Batteries are classified according to IEC classification standards: LR03 is equal to AAA, but in another standard.

This is a vibration noise which occurs when electric current flows through a transformer or a winding wire inside a component part. However, the charger may still be used without any concern as there is no need to worry from a safety point of view.

Due to chemical reactions inside most batteries, the stored charge of the batteries is reduced little by little. This phenomenon is called self-discharge.

In case of skin contact there is a chance of chemical burns. Use clear tepid water for at least 15 minutes on exposed skin. Consult a physician in case of irritation, injury or pain. In case of contact with the eye, do not rub the eyes, but flush with clear tepid water for at least 30 minutes and consult a medical professional immediately.

A hot battery could have several causes: from wrong storage to short circuiting. Some warmth is okay but keep an eye out for unusual heat.

A battery is a chemical product which produces electricity by chemical reactions at its inside. These reactions and its inside materials do deteriorate over time. If you start using it within that period, the battery will operate normally and maintain the specified performance.

Do not throw batteries in the trash. You can recycle every battery type you use - even unusable rechargeable batteries. Recycling points and regulations are different in every country.

As new energy flows into your battery, some heat is perfectly fine. If you notice the battery or charger becomes too hot to touch, cease the charging process immediately.

Make sure you measure the correct way: connect the poles to their corresponding measuring ends.

Yes. All batteries have an expiration date, beyond which their performance decreases.