Widely Used: This water level indicator is used for flower pots, a perfect tool for indoor and outdoor use Easy to use: No batteries or electricity needed, plug and use Easy observation: this water level indicator can show the water level to remind you to water and high quality. Important note: If there is no water in the pot, the buoy of the water level indicator is at the bottom. With that in mind, pull the water level and aquatic plants through the hole, Manufacturer: Littimoon