30 Litre Foam (AFFF) Mobile Fire AFFF Foam Mobile extinguisher is best suited to Class A and B fires. These fires include ordinary combustables such as wood, paper, plastics, rubber and rubbish aswell as flammable and combustable liquids such as petrol. The 30 Litre Foam mobile is the smallest of the range in terms of size with features that include a stainless steel cylinder, ultra high UV powder coated red finish and a galvanised red powder coated trolley.