A seal device (20) with a seal body (21) and an attachment device (22) for the captive attachment of the seal body to an object to be sealed, wherein one end of the attachment device is connected in a single piece with the seal body while its other end comprises a joining device (26) for non-positive joining to a connection device (27) that is provided on the seal body, wherein the seal body comprises a data carrier that comprises a data transmission device (32), which data carrier is designed as a switching circuit (23), wherein the switching circuit comprises an external circuit bridge (25) which for the purpose of connecting two connection points (29) of the switching circuit leads through the attachment device.