Parts List: 3×Scale plate 3×Indicator plate 12×Expansion tubes 12×Screws 3×Instruction manual Highlight description: Crack Monitor: The crack monitor consists of 2 plates with overlapping partial lengths. The bottom plate is calibrated in millimetres, the top plate is clear and marked with a crosshair cursor. Practical and convenient to use Accurate: The crack monitor with highly clear acrylic plate allows easy to read and watch the data. The scale plate is designed with scale in both horizontal and vertical directions. The Indicator plate has crossed indicator lines design Easy to Install: 2 plates can be easily fixed together without the need for glue or complicated installation steps. It is convenient and stable to use Practical: The crack monitor can be used for monitoring cracks in walls and their evolution over the measuring time Quality Acrylic: This crack monitor is crafted by quality acrylic, sturdy and enduring. And it is resistant to water; scratch and sun. Easy to install and reusable Detailed description: Description: This crack monitor consists of 2 plates with overlapping partial lengths. The 2 plates can be easily fixed together without the need for glue. It can used to monitor the cracks in the walls and how they evolved along the measured time Key Feature: Easy to Read: This crack monitor is designed with highly clear acrylic plate and scale in both horizontal and vertical directions that allows easy to read and watch the data Specification Name: Crack Monitor Material: Acrylic Size: 3cm Manual measurement may have 1-3cm Measuring range: -20~ +20mm Resolution: 1mm Measurement accuracy: ±1mm Note 1. There may be slight differences between the picture and the actual color of the commodity. We will try our best to show you the exact color 2. Please allow slight dimension difference due to manual measurement Easy to Install: 2 plates can be easily fixed together without the need for glue or complicated installation steps. It is convenient and stable to use Crack Monitor: The crack monitor consists of 2 plates with overlapping partial lengths. The bottom plate is calibrated in millimetres, the top plate is clear and marked with a crosshair cursor. Practical and convenient to use Accurate: The crack monitor with highly clear acrylic plate allows easy to read and watch the data. The scale plate is designed with scale in both horizontal and vertical directions. The Indicator plate has crossed indicator lines design Practical: The crack monitor can be used for monitoring cracks in walls and their evolution over the measuring time Quality Acrylic: This crack monitor is crafted by quality acrylic, sturdy and enduring. And it is resistant to water; scratch and sun. Easy to install and reusable