Bolts, Strongholds, Targets, Prisms

They are used for monitoring convergence of tunnels in construction and of underground cavities such as culverts and caves; examine plano-altimetric variations in outdoor excavations, landslides and unstable rock mass; supervise structural controls on buildings and infrastructures.
The use of topography accessories such as targets, levelling rods, bolts, prisms is ideal for monitoring. They are applied in geotechnical and structural monitoring, they are fixed on place, and keep long time excellent performance and accuracy.