While Elon Musk and Jeff Bezos are focusing on space, one billionaire is looking to profit from the water.

Ray Dalio, the founder of Bridgewater Associates, the world’s largest hedge fund, has invested in a firm that manufactures submarines for the super-rich

The price of the vessels varies from model range to capacity. The submarines are priced starting at $2.5 million and may go up to $40 million.