A device for removing a liquid or solid particles from a flat surface of a metal product, said device and said flat surface being adapted to move in a relative motion along a longitudinal path, the device comprising: - first and second feeding means (2', 2) for feeding gas jets along the width of the longitudinal path, arranged in a position proximal to said longitudinal path and to the surface of the metal product, - a casing containing a collection chamber for collecting liquid or solid particles removed from the flat surface of the metal product by means of said gas jets, wherein the first feeding means are configured so as to generate a first gas flow (Q 1) with a vectorial component in a sense opposite to the direction of said relative motion, and the second feeding means are configured so as to generate a second gas (Q 2) flow with a vectorial component in the same sense as the direction of said relative motion to direct the first flow within said collection chamber, wherein there are provided suction means (11 ') arranged at the side of the longitudinal path and substantially at said first and second feeding means (2', 2) wherein the collection chamber is central between the two feeding means (2', 2) and communicates at at least one side end of the device with said suction means, whereby the first and second flows produced in operation on the flat surface of the metal product by the jets and a third flow (Q x) aspirated from the external environment through a free section existing between the device and the flat surface of the metal product are diverted within the collection chamber so that the resulting flow (Q tot) moves away from the flat surface of the metal product, wherein said first and second feeding means (2', 2) are provided at ends (18, 18') of said casing, characterized in that said first and second gas jet feeding means respectively comprise a first tubular collector provided with a corresponding injection nozzle (5', 5) of the jet along its longitudinal extension, each injection nozzle (5',5) being spaced by a predetermined first distance (d2, d1) ranging from 5 mm to 100 mm from said path wherein the distance "d" between the two injection nozzles (5, 5') is comprised in the range from 5 to 2000 mm, the opening of the nozzles (5, 5') is comprised in the range from 1 to 10 mm, and the inclination angle (α, β) of the nozzles (5, 5') with respect to the feed plane of the strip is comprised in the range from 30o to 85o. - first and second feeding means (2', 2) for feeding gas jets along the width of the longitudinal path, arranged in a position proximal to said longitudinal path and to the surface of the metal product, - a casing containing a collection chamber for collecting liquid or solid particles removed from the flat surface of the metal product by means of said gas jets, wherein the first feeding means are configured so as to generate a first gas flow (Q 1) with a vectorial component in a sense opposite to the direction of said relative motion, and the second feeding means are configured so as to generate a second gas (Q 2) flow with a vectorial component in the same sense as the direction of said relative motion to direct the first flow within said collection chamber, wherein there are provided suction means (11 ') arranged at the side of the longitudinal path and substantially at said first and second feeding means (2', 2) wherein the collection chamber is central between the two feeding means (2', 2) and communicates at at least one side end of the device with said suction means, whereby the first and second flows produced in operation on the flat surface of the metal product by the jets and a third flow (Q x) aspirated from the external environment through a free section existing between the device and the flat surface of the metal product are diverted within the collection chamber so that the resulting flow (Q tot) moves away from the flat surface of the metal product, wherein said first and second feeding means (2', 2) are provided at ends (18, 18') of said casing, characterized in that said first and second gas jet feeding means respectively comprise a first tubular collector provided with a corresponding injection nozzle (5', 5) of the jet along its longitudinal extension, each injection nozzle (5',5) being spaced by a predetermined first distance (d2, d1) ranging from 5 mm to 100 mm from said path wherein the distance "d" between the two injection nozzles (5, 5') is comprised in the range from 5 to 2000 mm, the opening of the nozzles (5, 5') is comprised in the range from 1 to 10 mm, and the inclination angle (α, β) of the nozzles (5, 5') with respect to the feed plane of the strip is comprised in the range from 30o to 85o.