Put the onto the you want to measure, the middle position of bubble inside the will show that the is It will make easier and more for you to adjust the to the highest accurate Designed for decoration, home furnishings and related work for aligning, suitable for woodworking, processing, metal parts, installation pendant, the nails, door and window measurement from excellent acrylic materials, the glass has a light of 92 percentage so that the bubble will show the directly It has a wider application to showing the of measuring tool, industrial equipment, appliances, desktop, camera, and other places of higher accuracy, Manufacturer: RAFGALDEX