Abstract: A device for attaching a tube onto a holder includes the tube, the holder, a through screw and a nut, the holder receiving the tube in a cylindrical housing transversely pierced by a port, the tube having two piercings facing each other, the screw passing through the port and the two piercings and securing the tube and the holder, wherein the cylindrical housing of the holder has a longitudinal slot facing the port, the slot having two inner edges disposed on the side of the housing and two outer edges disposed on the side opposite the housing, the nut including at least one inclined face, each outer edge having a bell crank cooperating with the inclined face of the nut.