LED – the light-emitting portion of the LED system. There are three main diode types: mid-power, hi-power and chip-on-board (COB). All three can be found in LED grow light systems, though mid-power is the most common due to their low cost and high efficacy.

Driver – converts the AC power from a wall plug to DC power needed by the LEDs. It also controls the amount of power supplied to the LEDs. Most LED systems have an integrated driver that can accept an input voltage from 120-277V or 347-480V. 

Heat sink – a material in the LED system that absorbs heat produced by an LED. It spreads out and dissipates that heat into the air. These take many shapes and forms, but are typically used in a fin-like array on grow light systems. Without a heat sink, the LED will overheat and fail quickly.

Optics – LEDs inherently emit light as a “blob.” An optic can be added to focus the light into a desired shape or pattern. In doing so, the optics will absorb some of the light. However, not all LED systems will require an optic. They are most often used when precise control is needed based on the application or fixture design.