Assembly for terminating a corrugated conduit, comprising: - a box having a side wall and an aperture in the side wall, the side wall having an external surface facing outside the box and an internal surface facing inside the box; - a fitting assembly for connecting a corrugated conduit to the box, the fitting assembly comprising: i) a retaining member in the aperture, the retaining member comprising: - an annular portion housed inside the box and an inner cavity defined in the annular portion, the annular portion being mechanically engageable with the box and being configured to allow a corrugated conduit to be axially inserted in the inner cavity, the annular portion has an inner surface and an opposite outer surface, - at least one retaining wing axially extending from the annular portion outside of the box through the aperture and being resiliently deformable between an open position, allowing the axial movement of a corrugated conduit axially inserted in the inner cavity, and a lock position in which the retaining wing is mechanically engaged with the surface of the corrugated conduit, and ii) a fastener engageable with the retaining wing of the retaining member to maintain it in the lock position., characterised in that said outer surface engages by interference fit within the aperture, and in that the annular portion has a flange protruding outwardly from the outer surface and configured to abut against the internal surface of the side wall of the box. - a fitting assembly for connecting a corrugated conduit to the box, the fitting assembly comprising: i) a retaining member in the aperture, the retaining member comprising: - an annular portion housed inside the box and an inner cavity defined in the annular portion, the annular portion being mechanically engageable with the box and being configured to allow a corrugated conduit to be axially inserted in the inner cavity, the annular portion has an inner surface and an opposite outer surface, - at least one retaining wing axially extending from the annular portion outside of the box through the aperture and being resiliently deformable between an open position, allowing the axial movement of a corrugated conduit axially inserted in the inner cavity, and a lock position in which the retaining wing is mechanically engaged with the surface of the corrugated conduit, and ii) a fastener engageable with the retaining wing of the retaining member to maintain it in the lock position., characterised in that said outer surface engages by interference fit within the aperture, and in that the annular portion has a flange protruding outwardly from the outer surface and configured to abut against the internal surface of the side wall of the box. i) a retaining member in the aperture, the retaining member comprising: - an annular portion housed inside the box and an inner cavity defined in the annular portion, the annular portion being mechanically engageable with the box and being configured to allow a corrugated conduit to be axially inserted in the inner cavity, the annular portion has an inner surface and an opposite outer surface, - at least one retaining wing axially extending from the annular portion outside of the box through the aperture and being resiliently deformable between an open position, allowing the axial movement of a corrugated conduit axially inserted in the inner cavity, and a lock position in which the retaining wing is mechanically engaged with the surface of the corrugated conduit, and - an annular portion housed inside the box and an inner cavity defined in the annular portion, the annular portion being mechanically engageable with the box and being configured to allow a corrugated conduit to be axially inserted in the inner cavity, the annular portion has an inner surface and an opposite outer surface, - at least one retaining wing axially extending from the annular portion outside of the box through the aperture and being resiliently deformable between an open position, allowing the axial movement of a corrugated conduit axially inserted in the inner cavity, and a lock position in which the retaining wing is mechanically engaged with the surface of the corrugated conduit, and ii) a fastener engageable with the retaining wing of the retaining member to maintain it in the lock position., characterised in that said outer surface engages by interference fit within the aperture, and in that the annular portion has a flange protruding outwardly from the outer surface and configured to abut against the internal surface of the side wall of the box.