The GMXW0 is a mounting kit including a polystyrene mould that sits in the unset concrete. The polystyrene mould is mounted on a metal back plate with tapped mounting holes for the GM7xx seismic detectors. Once the concrete is set, the polystyrene can be carefully removed to expose a recess box. It offers sufficient space to install a GM7xx detector in the wall or the ceiling and provides access for cables via conduit to and from the detector.