When supplied by power from a Wire, the Signal Delay will wait a certain amount of time before outputting the signal. The amount of delay is indicated by the position of the white arrow along the black bar. Pressing the button will make the arrow go up slightly, increasing the delay. When the arrow reaches the top, it resets to the bottom. This functionality can be used to make automatic wood sorters.
This item acts similar to the Signal Sustain. The main difference is that while the Signal Delay preserves the duration of the signal, the Signal Sustain increases the duration of the signal.
The model of the Signal Delay is similar to that of the Signal Sustain, but the button function is different and the black bar has dividers. You can see the button function by moving your mouse over the button.