Relative or absolute angle measurement - Regular absolute measurement mode can measure angles of horizontal planes. The tool also has a relative measurement mode that quickly measures the angle between two measuring surfaces. Easy-to-read VA display and switchable unit - The clear and bright VA display allows you to use the device without light in the dark. The display mode can be converted from degrees (') to percentages (%), to (mm/m), to (IN/FT). Strong magnetic V-slot base and retention function - The V-slot base has powerful magnets that can be strongly attached to curved or cylindrical magnetic surfaces such as pipes or trees metallic. The hold function helps save the current angle on the screen. One key to switch between four units of angle, slope, mm/m, in/ft. Can be locked at any angle HOLD can hold measurement data at any angle Wide application - high quality tools for automotive, woodworking and mechanical industries, machinery, medical fields and more.