Earbuds charger case has a built in chip that protects your device from short circuit, over voltage, over current and over charge to ensure safe charging. Charging case is made of durable PC material and soft ABS plastic, which feels flat and durable and feels perfect in your hand. It is a great replacement to a lost or damaged charging case. When fully charged, the large battery size of the charging case can charge your earbuds up to 4 times. It is very convenient to charge at home, office, car or while traveling