Use Callout with RadToolTip
The RadCallout can be easily used as a tooltip. The code snippet in Example 1 shows how we can do this by using RadToolTip control.
Example 1: Place RadCallout Inside RadToolTip
<telerik:RadButton VerticalAlignment="Center" HorizontalAlignment="Center" Content="RadToolTip" Width="80"
telerik:RadToolTipService.ToolTipContentTemplate="{x:Null}"
telerik:RadToolTipService.Placement="Top"
telerik:RadToolTipService.HorizontalOffset="-20">
<telerik:RadToolTipService.ToolTipContent>
<telerik:RadCallout Content="Callout in a tooltip" Width="120" Margin="0 0 0 10"/>
</telerik:RadToolTipService.ToolTipContent>
</telerik:RadButton>