The Robinair LD7 Premium Refrigerant Leak Detectorsenses the most common refrigerants used today, including R-134a and R-1234yf. Two detection modes display proximity to leaks by either a bar graph or line graph. Audible chimes and visual graphs are to designed to help technicians locate leaks faster. Both modes allow for sweeping of a system, showing technicians when they get closer to a leak. An integrated UV LED light helps locate leaks when using UV dye for an all-in-one leak detection tool with a 10-year sensor life.