Links multiple window or door contacts into one state.

By linking several or all window or door contacts, you can conveniently check if all windows or doors are closed in the "ds Dashboard" app on your smartphone.
This state can also be used as condition e.g., in the Push Event Mailer app in order to check if everything is closed when leaving the house (activity'Leaving home'). If a window is still opened, your home sends you a Push Message automatically.