A carley float is like a giant circle-shaped life jacket for a boat. When a boat sinks, the carley float will float on the surface of the water to help keep people safe. It's made of strong materials that can withstand rough waves and wind. The carley float usually has handles on the outside to help people hold on, and sometimes a cover on top to help keep people dry. Think of it like a big, round, floating raft that can keep you safe in case of an emergency on your boat!