Eether, ither toggle or option control. The list of controls in the menu of the design bar calls it an option control. For the pedantic, maybe it is an option control being used as a toggle switch.
Looks like Y/N fields are always required. I don't use them. Most of the time I want tri-state options because yes and no mean something so I prefer the default to be null. That way, the user MUST make a choice because I define the integer field as required.