The LEDs are 'just' LEDs (albeit very nice ones); they don't need a controller to work.
Beware of the heat they produce though. The controllers are good as they allow you to turn them on just before flight (where the cooling is generally better) and turn them off straight afterwards. They also allow the more powerful LEDs to blink which also reduces the amount of heat they produce.
A simple RC switch can also work but uniLIGHT also have tiny 1 and 2 channel controllers available for simple installations.
