An optical adaptor for mounting to a receptacle to optically couple connectorized optical cables, comprising: - a coupling element to provide a passageway for inserting a ferrule of a first optical connector to terminate a first one of the connectorized optical cables and a ferrule of a second optical connector to terminate a second one of the connectorized optical cables to optically couple the first and the second connectorized optical cable (1, 2), - a mounting element mounted in a receptacle to hold the optical adaptor, the mounting element being configured to receive the coupling element, - wherein the mounting element is configured to mechanically couple the first optical connector to the mounting element so that the ferrule of the first optical connector intrudes in the passageway of the coupling element at a first side (S110a) of the coupling element, - wherein the coupling element has a second side (S110b) to mechanically couple the second optical connector to the coupling element such that the ferrule of the second optical connector intrudes in the passageway of the coupling element, - wherein the mounting element has a second side (S120b) with an opening to receive the second optical connector, - wherein a section of an outer surface of the mounting element is formed as a shoulder located between the first side (S120a) and the second side (S120b) of the mounting element, and the mounting element is formed with an inner tube extending at said first side (S120a) within the hollow body of the mounting element such that a small gap/channel for inserting a shroud of the first optical connector between an outer wall of the mounting element and the inner tube is formed, - wherein the mounting element is configured such that the shoulder abuts on the receptacle when the mounting element is mounted to the receptacle, - wherein the mounting element comprises a fixing means to mount the first optical connector to the mounting element. - a coupling element to provide a passageway for inserting a ferrule of a first optical connector to terminate a first one of the connectorized optical cables and a ferrule of a second optical connector to terminate a second one of the connectorized optical cables to optically couple the first and the second connectorized optical cable (1, 2), - a mounting element mounted in a receptacle to hold the optical adaptor, the mounting element being configured to receive the coupling element, - wherein the mounting element is configured to mechanically couple the first optical connector to the mounting element so that the ferrule of the first optical connector intrudes in the passageway of the coupling element at a first side (S110a) of the coupling element, - wherein the coupling element has a second side (S110b) to mechanically couple the second optical connector to the coupling element such that the ferrule of the second optical connector intrudes in the passageway of the coupling element, - wherein the mounting element has a second side (S120b) with an opening to receive the second optical connector, - wherein a section of an outer surface of the mounting element is formed as a shoulder located between the first side (S120a) and the second side (S120b) of the mounting element, and the mounting element is formed with an inner tube extending at said first side (S120a) within the hollow body of the mounting element such that a small gap/channel for inserting a shroud of the first optical connector between an outer wall of the mounting element and the inner tube is formed, - wherein the mounting element is configured such that the shoulder abuts on the receptacle when the mounting element is mounted to the receptacle, - wherein the mounting element comprises a fixing means to mount the first optical connector to the mounting element.