This specimen container is a rigid, see-through plastic vessel built to resist cracking and breakage during everyday aquarium use. A one-inch wide handle sits across the top so the unit can be hung on the rim of an existing aquarium or carried when moving fish between tanks. Because it hangs inside the main tank, it shares the surrounding water and can draw on the benefits of an existing heater rather than needing its own. Hobbyists use it as a temporary holding tank when catching or transferring fish, as a treatment container where a smaller water volume means less medication is needed, or simply as an observation chamber for a new arrival or a fish that looks unwell. No assembly is required; the container is ready to fill and hang as soon as it is unpacked. It is intended for indoor aquarium use and should be rinsed between uses to keep it clean for the next specimen.