A mask, comprising: a mask body having a width direction and a length direction; and a support made of bendable, lightweight and elastic plastic configured to support the mask body, the support comprising: one single longitudinal rib extending lengthwise; a single transversal rib body portion consisting of a first and second support rib portions extending from the middle of the longitudinal rib in opposite directions in the width direction such that the longitudinal rib and the transversal rib form a cross shape; a first sealing portion extending in the length direction of the body, attached at its middle to the end of the first support rib portion, having two free ends and configured to be fitted to a nose of a user; a second sealing portion extending in the length direction of the body, attached at its middle to the end of the second support rib portion, having two free ends and configured to be fitted to a jaw of a user; two third sealing portions extending in the width direction of the body, the first third sealing portion attached at its middle to a first end of the longitudinal rib, having two free ends and configured to be fitted to at least a part of the first cheek of a user, the second third sealing portion attached at its middle to the second end of the longitudinal rib, having two free ends and configured to be fitted to at least a part of the second cheek of a user; each of the first, second and third sealing portions comprising a fitting portion with a free end extending on either side. a mask body having a width direction and a length direction; and a support made of bendable, lightweight and elastic plastic configured to support the mask body, the support comprising: one single longitudinal rib extending lengthwise; a single transversal rib body portion consisting of a first and second support rib portions extending from the middle of the longitudinal rib in opposite directions in the width direction such that the longitudinal rib and the transversal rib form a cross shape; a first sealing portion extending in the length direction of the body, attached at its middle to the end of the first support rib portion, having two free ends and configured to be fitted to a nose of a user; a second sealing portion extending in the length direction of the body, attached at its middle to the end of the second support rib portion, having two free ends and configured to be fitted to a jaw of a user; two third sealing portions extending in the width direction of the body, the first third sealing portion attached at its middle to a first end of the longitudinal rib, having two free ends and configured to be fitted to at least a part of the first cheek of a user, the second third sealing portion attached at its middle to the second end of the longitudinal rib, having two free ends and configured to be fitted to at least a part of the second cheek of a user; each of the first, second and third sealing portions comprising a fitting portion with a free end extending on either side. a single transversal rib body portion consisting of a first and second support rib portions extending from the middle of the longitudinal rib in opposite directions in the width direction such that the longitudinal rib and the transversal rib form a cross shape; a first sealing portion extending in the length direction of the body, attached at its middle to the end of the first support rib portion, having two free ends and configured to be fitted to a nose of a user; a second sealing portion extending in the length direction of the body, attached at its middle to the end of the second support rib portion, having two free ends and configured to be fitted to a jaw of a user; two third sealing portions extending in the width direction of the body, the first third sealing portion attached at its middle to a first end of the longitudinal rib, having two free ends and configured to be fitted to at least a part of the first cheek of a user, the second third sealing portion attached at its middle to the second end of the longitudinal rib, having two free ends and configured to be fitted to at least a part of the second cheek of a user; each of the first, second and third sealing portions comprising a fitting portion with a free end extending on either side.