Durable acrylic construction Made from clear, high-strength acrylic for long-lasting use. Resistant to normal wear and tear and will not easily break or crack under typical field conditions. Clear, precise readings Transparent acrylic sheet with an easy-to-read measurement grid and crosshairs provides clear visual reference for tracking crack movement. Scale markings let you record small displacements reliably. Two-direction displacement monitoring Measuring scale and crosshairs show displacement in both top-bottom and left-right directions, so you can monitor lateral and vertical movement from a single device. Simple, reliable installation Mounting is straightforward: align the crack with the center crosshair, secure the gauge with the two adapters, then fasten to the wall using screws and expansion screws. Designed for hassle-free attachment to concrete and masonry surfaces. Practical compatibility and performance Intended for use on concrete and masonry walls where ongoing crack measurement is needed. The combination of a clear acrylic sheet and a calibrated grid ensures repeatable, readable measurements without specialized tools. Typical use scenarios Building maintenance: Monitor hairline and structural cracks over time to determine whether repairs are needed or if movement is stabilizing. Post-event inspection: Track crack displacement after events such as earthquakes or foundation settlement to document ongoing movement. Renovation and site monitoring: Use during renovation or construction to confirm whether adjacent work affects existing cracks. What it delivers Durable material, clear visual measurement, two-axis displacement tracking, and a straightforward installation process for consistent, on-site monitoring of concrete and masonry cracks.