Respiratory mask comprising a mask body and a flexible cushion detachably attached to the mask body , characterized in that : - the mask body comprises a first and a second tubular structure , said first and second tubular structures being coaxially arranged and spaced apart from each other by a first annular lodging , wherein : • the first tubular structure has a first inner diameter D1 and the second tubular structure has a second inner diameter D2 with D1<D2, • and the second tubular structure comprises at least a notch , - the flexible cushion comprises a third and a fourth tubular structure , said third and fourth tubular structures being coaxially arranged and spaced apart from each other by a second annular lodging , wherein : • the third tubular structure has a third inner diameter D3 and the fourth tubular structure has a fourth inner diameter D4 with D3<D4 and D4>D2>D3>D1, • and at least a protruding element is arranged in the second annular lodging , and wherein, when the flexible cushion is attached to the mask body : - the second tubular structure of the mask body is inserted into the second annular lodging of the flexible cushion and held therein by the third and fourth tubular structures of the flexible cushion , - the third tubular structure of the flexible cushion is inserted into the first annular lodging of the mask body and held therein by the first and second tubular structures of the mask body , and - the protruding element is at least partially lodged into the notch . - the mask body comprises a first and a second tubular structure , said first and second tubular structures being coaxially arranged and spaced apart from each other by a first annular lodging , wherein : • the first tubular structure has a first inner diameter D1 and the second tubular structure has a second inner diameter D2 with D1<D2, • and the second tubular structure comprises at least a notch , • the first tubular structure has a first inner diameter D1 and the second tubular structure has a second inner diameter D2 with D1<D2, • and the second tubular structure comprises at least a notch , - the flexible cushion comprises a third and a fourth tubular structure , said third and fourth tubular structures being coaxially arranged and spaced apart from each other by a second annular lodging , wherein : • the third tubular structure has a third inner diameter D3 and the fourth tubular structure has a fourth inner diameter D4 with D3<D4 and D4>D2>D3>D1, • and at least a protruding element is arranged in the second annular lodging , • the third tubular structure has a third inner diameter D3 and the fourth tubular structure has a fourth inner diameter D4 with D3<D4 and D4>D2>D3>D1, • and at least a protruding element is arranged in the second annular lodging , - the second tubular structure of the mask body is inserted into the second annular lodging of the flexible cushion and held therein by the third and fourth tubular structures of the flexible cushion , - the third tubular structure of the flexible cushion is inserted into the first annular lodging of the mask body and held therein by the first and second tubular structures of the mask body , and - the protruding element is at least partially lodged into the notch . <EOS>