GeoMax L-Bar Monitoring PrismGeoMax L Bar Monitoring Prism Features The L Bar Monitoring Prism is a compact and versatile optical target used with automated total stations (AMTS) to monitor displacements and deformations of structures Suitable for a wide range of applications, the L Bar Monitoring Prism can be installed on tunnel walls, building facades, foundation slabs, retaining walls and bridge decks The prism offset is dependent on the mounting position Range 2000 m (7000 ft)