ZeroR UV Dye Leak Detector 1 Can is enough dye for a full size auto or truck Can has R134a_ thread on can top For use in automotive applications ZeroR UV Dye Leak Detector is fully compatible with mineral, ester and pag oils. Highly concentrated dye (fluorescent yellow) works best with the use of a black light and UV glasses Returns: This item is considered a HazMat Material and as such is not returnable. It requires hazmat certification to ship. Amazon does not supply a Return label and the seller will not supply return labels for this type of products. Please contact seller for any help you might need in using the product. ZeroR Refrigerant_ with Dye is fully compatible with mineral-pag-ester oils and is specifically designed to assist you in locating air conditioning leaks that may occur in your air conditioning system. A precisely selected color highly concentrated UV dye (fluorescent yellow) is utilized and allows the dye to be highly visible. In most cases, the dye may be seen with the naked eye. However, the use of a blacklight as well as UV glasses does make it much more visible. This dye is the same color as the dye that auto makers currently use in automobile AC systems. ZeroR Refrigerant_ with Dye 2 oz. product--connects to regular system with a 134a_ tap