Powering one Flex II bar gets no simpler than this. The 25 watt adapter plugs into a wall socket and runs a single Flex II 25, a single Flex II 20 or a pair of Flex II 10 bars. There is no boxed driver to find a home for, which suits a lone propagation shelf or a small cutting station.
The adapter cable is in the box, so it works the moment you unpack it.