cbar-button-group is an element that groups buttons together and makes them toggleable as a group, much like a group of radio buttons.
Example:
<div id="container">
<cbar-button-group
selected="option 2"
attr-for-selected="name"
selected-attribute="active">
<button name="option 1">Option 1</button>
<button name="option 2">Option 2</button>
<button name="option 3">Option 3</button>
</cbar-button-group>
</div>