My friend was going scuba diving on an island without power. He bought and tested 5 different brands on Amazon. Anker was the best. He had an extra battery,

My friend was going scuba diving on an island without power. He bought and tested 5 different brands on Amazon. Anker was the best. He had an extra battery, so I bought it from it. It was worked wonders when I am traveling for the day and need to charge my phone.