Swellpro Splash Drone 3 is a valuable tool for water rescue, to bring PFD (Personal Flotation Device) or a life jacket to a stranded victim through it's payload release system. Aside from that, it's waterproof and can float on water. Here's a video of a practice drill on bringing a life jacket to a stranded patient.
Swellpro Splash Drone is available at Urban Drones. Urban Drones is located in the U.S.A and is the service center for the Splash Drone Service, support and sales.