Abstract: An alarm device includes a portable alarm emitter, the portable alarm emitter being configured to detect a change in an electrical property of a sensor element which is connected to the portable alarm emitter and to signal an alarm if a change is established. The portable alarm emitter and the sensor element are separate units configured to be interconnected with electrical contact. The portable alarm emitter is a reusable unit. The sensor element has an end which is formed as an eye through which an other end of the sensor element can be passed in order to form a closed loop which can only be made smaller because of a one-way locking function of the eye, the sensor element having at least one line element which can be contacted after the other end is introduced into the alarm emitter.

Abstract: A receiving container, and method of using the same, for packet or small parcel mailings to be received or to be sent, having a closable opening through which a packet or small parcel mailing can be inserted into the receiving container. The receiving container has a fixing element with which the receiving container can either be fixed to, or removed from, a door of a house or an apartment, in particular without structural work in each case.

Abstract: An alarm device includes a portable alarm emitter, the portable alarm emitter being configured to detect a change in an electrical property of a sensor element which is connected to the portable alarm emitter and to signal an alarm if a change is established. The portable alarm emitter and the sensor element are separate units configured to be interconnected with electrical contact. The portable alarm emitter is a reusable unit. The sensor element is a disposable unit.