These Dye Lite fluorescent dyes are specially formulated for oil and petroleum based fluid systems. The dye is added to the system by simply pouring it into the fill port. This multipurpose dye has over twice the amount of active ingredients as competitors dyes so only half as much is needed for most applications! These dyes pinpoint even the smallest oil leaks. They can be used to detect leaks in engine oils (gasoline & diesel) fuel (gasoline & diesel) automatic transmission fluids power steering fluids and hydraulic fluids. Its unique full spectrum formulation glows brightly with both UV and blue light lamps. Super concentrated and very economical. Includes six 1 oz. bottles.