Coaxial connector system comprising a coaxial plug connector and a coaxial socket connector, the coaxial plug connector comprising at least - a center conductor defining a center axis of the coaxial plug connector, - an outer conductor coaxial to the center conductor, the outer conductor having a basically cylindrical shape with slits forming a plurality of spring loaded contact elements, - a mechanical contact surface at a right angle to the center axis and distant from the spring loaded contact elements to define the spatial relationship of the coaxial plug connector and the coaxial socket connector in the direction of the center axis, when the connectors are mated, - at least one precision centering means for aligning the center axis of the coaxial plug connector to a center axis of the mating coaxial socket connector, the at least one precision centering means has a cylindrical outer contour which is precision machined and matches to the at least one precision centering means of the coaxial socket connector, and - an O-ring for sealing a gap between the coaxial plug connector outer conductor and a coaxial socket connector outer conductor when mated, the coaxial socket connector comprising at least - a center conductor defining a center axis of the coaxial socket connector, - the outer conductor coaxial to the center conductor, the outer conductor having a basically cylindrical shape with a contact surface, - a mechanical contact surface at a right angle to the center axis and distant from the contact surface to define the spatial relationship of the coaxial socket connector and the coaxial plug connector in the direction of the center axis, when the connectors are mated, - the at least one precision centering means for aligning the center axis of the coaxial socket connector to the center axis of the mating coaxial plug connector, the at least one precision centering means has a cylindrical inner contour which is precision machined and matches to the at least one precision centering means of the coaxial plug connector, and - a circular protrusion close to the contact surface which has the same inner diameter as the spring loaded contact elements of the coaxial plug connector. - a center conductor defining a center axis of the coaxial plug connector, - an outer conductor coaxial to the center conductor, the outer conductor having a basically cylindrical shape with slits forming a plurality of spring loaded contact elements, - a mechanical contact surface at a right angle to the center axis and distant from the spring loaded contact elements to define the spatial relationship of the coaxial plug connector and the coaxial socket connector in the direction of the center axis, when the connectors are mated, - at least one precision centering means for aligning the center axis of the coaxial plug connector to a center axis of the mating coaxial socket connector, the at least one precision centering means has a cylindrical outer contour which is precision machined and matches to the at least one precision centering means of the coaxial socket connector, and - an O-ring for sealing a gap between the coaxial plug connector outer conductor and a coaxial socket connector outer conductor when mated, the coaxial socket connector comprising at least - a center conductor defining a center axis of the coaxial socket connector, - the outer conductor coaxial to the center conductor, the outer conductor having a basically cylindrical shape with a contact surface, - a mechanical contact surface at a right angle to the center axis and distant from the contact surface to define the spatial relationship of the coaxial socket connector and the coaxial plug connector in the direction of the center axis, when the connectors are mated, - the at least one precision centering means for aligning the center axis of the coaxial socket connector to the center axis of the mating coaxial plug connector, the at least one precision centering means has a cylindrical inner contour which is precision machined and matches to the at least one precision centering means of the coaxial plug connector, and - a circular protrusion close to the contact surface which has the same inner diameter as the spring loaded contact elements of the coaxial plug connector.