LeakFinder® ultraviolet fluorescent universal dyes provide the most precise leak detection for all automotive air conditioning systems containing R-134a, R-1234yf, or other widely used refrigerants. These specialty dyes can be safely added to the system. They won’t affect your system’s lubricant properties or change how the equipment works. LeakFinder® dyes find the smallest and most problematic leaks that would otherwise be impossible to detect. Compatible with R-134a, R-1234yf, and other Refrigerants 1 oz (30 ml) Bottle (Services up to 4 Vehicles) 8 oz (237 ml) Bottle (Services up to 32 Vehicles) Fluoresces Green Works with All Leak Detection Flashlights .