With its 2 in 1 formula, Etha-Guard Plus with Octimise Plus friction modifier stabilises E5 & E10 ethanol petrol keeping your fuel system clean and corrosion free whilst delivering enhanced performance and economy with up to 3% increased acceleration and up to 2% improved fuel economy. Protects your vehicle in use or storage; also prevents damage to fibreglass fuel tanks. Fully compatible with vehicles fitted with catalytic converters, offering the best protection against ethanol damage for drivers of younger and modern classics not requiring valve seat protection. Counteracts ethanol's hygroscopic nature, preventing moisture and subsequent acidity in your fuel system protecting both in use and in storage, stabilising the fuel to prevent moisture absorption and separation. (Note: all products in the Valvemaster Fuel Additive range contain Etha-Guard). 250ml Bottle treats 250 Litres of fuel