According to dpReview, it’s the Panasonic Lumix DMC-TS3:
If you plan to spend a significant amount of time underwater, or in other types of adverse conditions, the Panasonic TS3 is without a doubt the strongest performer in this group. It is one of the toughest cameras in this group, but crucially, it is also one of the best. We love its chunky controls, simple menu, and excellent still and video image quality.
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