Menu radio item. Similar to TMenuItemChecked, but it belongs to a group and within this group only one (or none) radio button can be checked.
Note that AutoCheckedToggle property has a little different meaning in this class: whenever user will click on some item, it will be automatically set to Checked = True and the rest of items within this group will be set to Checked = False.
You can of course operate on Checked property explicitly, setting it to True or False.