Light controllers help you set up gardens with many lights.

Light controllers help you set up gardens with many lights. These light controller boxes can help you turn multiple lights on and off simultaneously, or at different times depending on the parameters you set.

Some light controllers do not have a built-in timer--for these units, there is an input plug for a 24-hour timer that will act as the timer for the unit.
This allows you to have a high-amperage light controller with an inexpensive low-amperage timer.