Many people are uncomfortable leaving their keys on the beach;and for good reason. It’s best to bring your keys in the water with you — which is no problem if you have a standard metal key. However, many late-model cars have keys with electronic components that can’t get wet. If you’ve chosen a combination dive flag/snorkeling bag, you can leave your keys in the flag component that stays over the water. If not, it’s best to look for a waterproof container that attaches to a belt so you can keep your keys with you at all times.