Product Description hanging water fountain replaces traditional spring-mounted water bottles and bowls for a more comfortable drinking experience for your little pet. SCIENTIFIC WAY OF DRINKING WATER Drinking from a water bowl is a more scientific and comfortable way for small animals. And relatively small outlets won t cause your pet to develop mouth infections. HANGING WATER FOUNTAIN Hanging the water fountain at the right height will prevent your pet from developing neck spondylopathy due to drink with their head up all the time. NO LEAK The siphon design of the bottleneck can control the amount of water output and prevent the overflow. LARGE CAPACITY OF 500ml If you have several pets or an adult rabbit 500ml water is enough for them to drink in a day. It is suitable for rabbits chinchillas hamsters guinea pigs squirrels and other small animals but it is not suitable for dwarf hamsters. REQUIREMENT FOR CAGES If you want to install it outside your cage the grid spacing should be between 0.86in(2.2cm)-1.9in(5cm); If you want to install it inside your cage the grid spacing should be between 0.6in(1.5cm)-1.9in(5cm).