System for dispensing a liquid foam, in particular a direct foam cleaning product, comprising a container for the liquid and a dispensing apparatus (1; 101; 201) connected to the container, wherein the dispensing apparatus (1; 101; 201) comprises: - a pump comprising a pump chamber (20; 120; 220) in fluid communication with the container and a piston (22; 122; 222) arranged in the pump chamber (20; 120; 220), the piston (22; 122; 222) and pump chamber (20; 120; 220) being movable with respect to one another; - an outlet channel (60; 160; 260) connecting the pump chamber (20; 120; 220) to a nozzle (50; 150; 250) which includes an orifice, - a pre-compression valve (40; 140; 240) arranged between the outlet channel (60; 160; 260) and the nozzle (50; 150; 250), and - a buffer comprising a buffer chamber (30; 130; 230) connected to the outlet channel (60; 160; 260), the buffer chamber (30; 130; 230) including a compressible variator (70; 170; 270) arranged therein for varying the usable volume of the buffer chamber (30; 130; 230), characterized in that: the nozzle (50; 150; 250), the buffer and the pump are configured and dimensioned such that the foam is dispensed from the nozzle orifice in a predetermined spray pattern, the pre-compression valve (40; 140; 240) and the buffer chamber (30; 130; 230) are arranged to define lower and upper limits, respectively, of a dispensing pressure of the foam, the pre-compression valve (40; 140; 240) having a cracking pressure of about 200 to 450 kPa (2 to 4.5 bar), preferably about 300 to 350 kPa (3 to 3.5 bar), and the nozzle (50; 150; 250) has a divergent expansion area downstream of the nozzle orifice, wherein the expansion area: has aeration openings, and is conical and has a top angle of between about 20-120°, preferably between about 30-90°, and more preferably about 50°. - a pump comprising a pump chamber (20; 120; 220) in fluid communication with the container and a piston (22; 122; 222) arranged in the pump chamber (20; 120; 220), the piston (22; 122; 222) and pump chamber (20; 120; 220) being movable with respect to one another; - an outlet channel (60; 160; 260) connecting the pump chamber (20; 120; 220) to a nozzle (50; 150; 250) which includes an orifice, - a pre-compression valve (40; 140; 240) arranged between the outlet channel (60; 160; 260) and the nozzle (50; 150; 250), and - a buffer comprising a buffer chamber (30; 130; 230) connected to the outlet channel (60; 160; 260), the buffer chamber (30; 130; 230) including a compressible variator (70; 170; 270) arranged therein for varying the usable volume of the buffer chamber (30; 130; 230), the nozzle (50; 150; 250), the buffer and the pump are configured and dimensioned such that the foam is dispensed from the nozzle orifice in a predetermined spray pattern, the pre-compression valve (40; 140; 240) and the buffer chamber (30; 130; 230) are arranged to define lower and upper limits, respectively, of a dispensing pressure of the foam, the pre-compression valve (40; 140; 240) having a cracking pressure of about 200 to 450 kPa (2 to 4.5 bar), preferably about 300 to 350 kPa (3 to 3.5 bar), and the nozzle (50; 150; 250) has a divergent expansion area downstream of the nozzle orifice, wherein the expansion area: has aeration openings, and is conical and has a top angle of between about 20-120°, preferably between about 30-90°, and more preferably about 50°. has aeration openings, and is conical and has a top angle of between about 20-120°, preferably between about 30-90°, and more preferably about 50°.