This feeder holds about 1L of syrup and goes inside your hive, sitting on top of the crown board and under he lid, so its perfect for flow hives. 

As its inside your hive so there can be no problem with ants or robber bees stealing the syrup. It's a ladder style feeder so the bees climb down a ladder to the syrup and are less likely to drown. for a video of this in use click here https://www.youtube.com/watch?v=0dCPvi0iCaQ