Crack Monitoring Telling about Crack Monitor Simple and cool analog crack monitoring device.1 mm (0.04") graticule on X-Y axis; 0.5 mm (0.02") resolution20 mm (0.79") horizontal range and 10 mm (0.38") vertical rangeHigh-quality polymer with easy-to-read measuring gridCrack monitoring scales are used to monitor cracks in walls and their evolution over a measured time.parameter: Material: acrylic Size: 10*3*0.9cm Weight: 36 grams Packaging: OPP Purpose: Can be used to monitor wall deformation/cracks Packing list: 1 pair of monitors + 4 screws + 1 monitoring table Features: 1. Easy to install, waterproof, sunproof, wear-resistant and scratch-resistant 2.1:1 original export, high transparent acrylic plate is clear and precise 3. Crack monitoring gauges are used to monitor cracks in walls and how they evolve over time by measuring