# Graphical Panel Controls: Radio Button

Radio buttons allow the user of a graphical panel to select from among a small list of available options, much like the buttons on old car stereos.\
\
These controls are usually used in groups by linking multiple radio buttons to the same signal. When one radio button tied to a particular signal is clicked, the value associated with that button is assigned to the signal. At the same time, any other radio buttons linked to that signal are de-selected, so that only one can ever be selected at a time. An example of a cluster of three radio buttons can be seen in Figure 1.

Multiple groups of radio buttons can be used to enable easy selection of options for multiple signals.

![Figure 1: A set of three radio buttons linked to a signal. Selecting any option de-selects the others.](/files/jQ101sTnF7tktXfQDjj2)

A list of common properties can be found under [Common Control Properties](/vspy-3-documentation/vehicle-spy-main-menus/main-menu-measurement/graphical-panels/graphical-panels-tools/graphical-panel-controls-common-control-properties.md). Table 1 describes the single additional property for the Radio Button control.

**Table 1: Radio Button Control Properties**

| Property | Function and Options                                                      |
| -------- | ------------------------------------------------------------------------- |
| Value    | Sets the value returned to the linked signal when the button is selected. |


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