These are perfect to protect you shrimp and small fish when doing water changes. Just attach the filter to the tank's end of the hose prior to water drainage. This will protect the small animals inside the time.
Please Note: This is intended for small hoses used in Nano and Shrimp tanks.
Small is 2.5 inches long and will support hoses about .36 inches ( 9mm)
Large is 3.5 inches long and will support hoses about .55 inches (14mm)
