Shown is a 4 circuit CHASE. It is 4 circuits because there are four tubes, all lighting independently from each other.
This example of a CHASE pattern is called a "Dark Chase" because only one circuit (neon tube in our example) is lit at a time. This is also referred to as "1 On/3 Off" chase pattern. Compared to a Bright Chase, which is 3 On/1 Off, a Dark Chase is usually preferred because the chasing effect is more distinct. In addition, a Dark Chase unit is usually less expensive because, with only one circuit being on at a time, the unit can be made to handle a lesser load.
The most common CHASE units are 3 and 4 circuits, however chase units can be many multiples of circuits. A 2 circuit unit will not typically achieve an appealing CHASE pattern and is rarely, if ever used.
You can have the chase pattern go from left to right, or right to left, simply by how you wire up the Chase unit.
