Manual filigree work requires top precision and a sharp eye. Magnifying glasses are a tried and tested tool for increasing precision, quality and the speed of work or maintenance. Line testers are another tool that has a wide range of applications due to their compact design. For example, they can be used to check the quality of materials in the textile industry, or to see if there are production faults in PCBs. Special workshops, like watchmakers, particularly need magnifying glasses. They are equipped with special lenses that make it possible to see and work with even the smallest structures. Measuring magnifiers or adjustable head magnifying glasses are used in industry, laboratories and education. Illuminated pocket magnifying glasses are useful for reading and they are used for work in workshops, for example.