I finally had a chance to take mine in the water. I think they are loud enough for me. I had boats and wind but could hear fine. Comfortable enough to wear for a while. Cord was long enough. I have not submerged them, that comes over the next few days. The description in the eBay listing for mine was that they have the Visaton waterproof diaphragm loudspeakers.
BTW, they haven’t increased my finds magically yet ?