1. Extended Battery Life: The 4500mAh capacity significantly boosts the phone's battery life, allowing for additional hours of usage (calls, video streaming, gaming, etc.).
2. Protection: In addition to charging, the case also acts as a protective cover, safeguarding the iPhone against scratches, drops, and minor impacts.
3. Convenience: Users can charge their phone and the case simultaneously, and some models feature LED indicators to show battery levels of the case.
4. Design: Most of these cases are designed to be slim and lightweight, though they are bulkier than regular phone cases due to the extra battery capacity.
5. Compatibility: Available for different iPhone models, these battery cases are tailored to fit securely and provide easy access to ports, buttons, and cameras.

A 4500mAh battery case is ideal for those who frequently use their phone throughout the day and need extra power without carrying an external charger.