BIG RIG Cannon Foam is a premium concentrated high-foaming liquid detergent formulated with the highest quality penetrants and surfactants to promote rapid emulsification of dirt, oil, grease and road grime. It's well-suited for trucks, trailers, RVs, buses and other heavy equipment. This detergent is especially formulated for use in high-pressure washing equipment with foaming cannons. BIG RIG Cannon Foam is especially suited for trucks, trailers, RVs, buses and other heavy equipment. This detergent is especially formulated for use in high-pressure washing equipment with foaming cannons.