Casio G-Shock Watch - Red - GM-2100B-4APR

While it is water-resistant and suitable for swimming or snorkeling, it is not designed for professional deep-sea or scuba diving.

Yes, standard G-Shock models in this series typically feature an integrated light for visibility in low-light conditions.

Yes, the resin strap can be replaced with compatible G-Shock bands if needed.

Battery life varies based on usage but typically lasts several years under standard operating conditions.

It is designed to be highly shock-resistant, meaning it can withstand significant impacts compared to a standard wristwatch.

The internal battery may be depleted; take the watch to an authorized service center for a battery change.

This suggests a compromised seal; avoid further water exposure and have the gaskets inspected by a professional.

Ensure the strap is not fastened too tightly to allow for airflow, and adjust the buckle to the next available hole.