DEMA 294 models mix chemical solution with water and air to produce a dry, thick, clinging foam to any vertical or horizontal surface. The 294 is excellent for cleaning large spaces and areas that require foam to penetrate for better cleaning results. The foam consistency is changed easily by adjusting either the air or water pressure. Units require compressed air and at least 40 psi water pressure to produce quality foam. Multiple models are available with a variety of features.