Practical Design: Consisting of two overlapping plates, the base plate has millimeter scale while the clear top plate features a crosshairs for accurate alignment and measurement Clear Measurement: Featuring a high transparency acrylic panel with easy to read measurement grids, this cracks monitor provides clear and readings for practical applications Acrylic Construction: The cracks monitor is made from acrylic, ensuring durability, smooth surfaces, wear resistance, and resistance to breakage for long term use Wide Application: Designed for 2D artificial cracks, this tool effectively tracks wall cracks and their changes over time in buildings and structures cracks: This simple yet stylish analog device accurately monitors horizontal or vertical displacement of cracks, making it an essential tool for structural assessment, Manufacturer: Hsyzygian