Abstract: An attachment system for a door or window, the attachment system being configured to sense a condition of a door or window, the attachment system including: a securing member configured to be mounted to a frame member of the door or window; and a module, configured to be coupled to a frame member by attachment to the securing member, the module including a sensor to sense the condition of the door or window, and the securing member including a resiliently biased clip configured to retain the module in attachment to the securing member selectively, wherein the securing member is configured space the module from at least part of the frame member such that the sensor is positioned to sense the condition of the door or window.

Abstract: A lock indicator and a mechanical lock assembly, comprising: a switch; a transmitter coupled to a power source; and a bolt member moveable between a retracted position and an extended position with respect to the housing, wherein the switch is configured to engage the bolt member and is actuatable by the bolt member to determine the position of the bolt member, and the transmitter is configured to transmit a signal indicative of the position of the bolt member to a remote device.