A device for spraying a coating product in liquid form, comprising: - means for spraying the liquid product, - a valve for controlling the flow of the liquid product towards the spraying means, the valve being actuated by a control fluid and comprising: - a piston arranged to be moved by the control fluid between a top dead center and a bottom dead center, - a needle secured to the piston and arranged to release or obturate a liquid product passage towards the spraying means, - a valve body comprising a housing arranged to house the piston, and comprising a control fluid supply connector arranged on the side of the bottom dead center, the valve body is monolithic and further comprises at least one control fluid supply channel (12, 13) formed in a side wall of the valve body and of which at least one longitudinal portion extends along part of the housing from the side of the supply connector to the side of the top dead center, and said at least one supply channel (12, 13) further comprises: - a portion on the bottom dead center side below the bottom dead center extending along a direction having a radial component and connecting the supply connector to the longitudinal portion, and - a portion on the top dead center side extending along a direction having a radial component connected to the longitudinal portion and comprising an exhaust hole (12a, 13a) opening out into the housing of the valve body beyond the top dead center, so as to allow the return of the piston, and the device being characterized in that the valve body comprises a plurality of control fluid supply channels (12, 13) housed in the wall of the valve body. - means for spraying the liquid product, - a valve for controlling the flow of the liquid product towards the spraying means, the valve being actuated by a control fluid and comprising: - a piston arranged to be moved by the control fluid between a top dead center and a bottom dead center, - a needle secured to the piston and arranged to release or obturate a liquid product passage towards the spraying means, - a valve body comprising a housing arranged to house the piston, and comprising a control fluid supply connector arranged on the side of the bottom dead center, - a piston arranged to be moved by the control fluid between a top dead center and a bottom dead center, - a needle secured to the piston and arranged to release or obturate a liquid product passage towards the spraying means, - a valve body comprising a housing arranged to house the piston, and comprising a control fluid supply connector arranged on the side of the bottom dead center, the valve body is monolithic and further comprises at least one control fluid supply channel (12, 13) formed in a side wall of the valve body and of which at least one longitudinal portion extends along part of the housing from the side of the supply connector to the side of the top dead center, and said at least one supply channel (12, 13) further comprises: - a portion on the bottom dead center side below the bottom dead center extending along a direction having a radial component and connecting the supply connector to the longitudinal portion, and - a portion on the top dead center side extending along a direction having a radial component connected to the longitudinal portion and comprising an exhaust hole (12a, 13a) opening out into the housing of the valve body beyond the top dead center, so as to allow the return of the piston, and - a portion on the bottom dead center side below the bottom dead center extending along a direction having a radial component and connecting the supply connector to the longitudinal portion, and - a portion on the top dead center side extending along a direction having a radial component connected to the longitudinal portion and comprising an exhaust hole (12a, 13a) opening out into the housing of the valve body beyond the top dead center, so as to allow the return of the piston, and the device being characterized in that the valve body comprises a plurality of control fluid supply channels (12, 13) housed in the wall of the valve body.