These are large bronze ship propellers, likely for a commercial vessel or submarine. The visual evidence suggests they are in a salvage yard or a marine engineering workshop, possibly for repair, maintenance, or scrap. The size and design of the propellers indicate they are intended for a large watercraft, such as a cargo ship, yacht, or even a submarine, as similar propellers are used on those types of vessels. Propellers of this size are typically made of bronze, an alloy that is strong and corrosion-resistant.