Probably the most economical coolant for VW and other European vehicles. I don't know if there's a VW spec that requires testing and certification, but it's essentially the same as Pentafrost. I can't remember if my research showed it to be G12, G12+/++ or G13, but it was one of them. Basically, if you have a European car with diesel engines from the 1990s to 2015 or so, this is a great deal. Does NOT contain 2EHA (2-Ethylhexanoic Acid) found in HOAT and OAT compatible Dex-Cool and Dex-Cool coolants which can corrode seals and cause problems.