Blue Pentosin G11 in 1.5 Liter bottles. G11 can only be mixed with blue or green antifreeze. Mix 1 to 1 with distilled water for best results. Pentosin Antifreeze is specifically designed for use is aluminum block motors. G11 coolant helps prevent corrosion of aluminum alloys and the formation of scale. Pentosin G11 is compatible with all VW/Audi vehicles up to 06/1996 that do not use pink G12 coolant from the factory. Check your owners or shop manual, or contact us if unsure what to use.