Also known as: クスコ, 鸭嘴钳, 扩阴器, 窥器
A medical tool for inspecting body cavities, especially the vagina.
In Japanese culture, it is popularized by its frequent usage in Pornography as a tool to inspect the AV actresses' vagina to confirm an internal ejaculation. It is also often generally called クスコ (cusco, Cusco's speculum).