Plug connector for attaching to or plugging into a mating plug connector having at least two mating contact elements along a plug-in direction, wherein the plug connector has a housing having a first plane which faces the plug-in direction; wherein the housing has at least two contact chambers, each of the latter having an opening in the first plane, wherein each contact chamber is specified to receive one contact element that is specified to electrically and mechanically contact one of the at least two mating contact elements of the mating plug connector; wherein a contact locking element is disposed on the first plane, for locking the contact elements which are able to be introduced into the contact chamber, wherein at least two of the contact chambers are configured so as to be separate from one another in the housing; wherein a wall, which when viewed counter to the plug-in direction protrudes from the first plane, is disposed between at least two mutually adjacent contact chambers; and/or wherein at least one groove is disposed in the first plane between at least two mutually adjacent contact chambers, characterized in that the housing has an outer rim which borders the first plane and, counter to the plug-in direction, protrudes beyond the first plane; wherein the rim borders the first plane along an encirclement angle (φ) of at least 220° about the plug-in direction, wherein the wall and/or the at least one groove is/are routed along a radial direction, perpendicular to the plug-in direction, through the rim; wherein a clearance is in each case provided along an encircling direction on both sides of the wall, between the rim and the wall. wherein the plug connector has a housing having a first plane which faces the plug-in direction; wherein the housing has at least two contact chambers, each of the latter having an opening in the first plane, wherein each contact chamber is specified to receive one contact element that is specified to electrically and mechanically contact one of the at least two mating contact elements of the mating plug connector; wherein a contact locking element is disposed on the first plane, for locking the contact elements which are able to be introduced into the contact chamber, wherein at least two of the contact chambers are configured so as to be separate from one another in the housing; wherein a wall, which when viewed counter to the plug-in direction protrudes from the first plane, is disposed between at least two mutually adjacent contact chambers; and/or wherein at least one groove is disposed in the first plane between at least two mutually adjacent contact chambers, characterized in that the housing has an outer rim which borders the first plane and, counter to the plug-in direction, protrudes beyond the first plane; wherein the rim borders the first plane along an encirclement angle (φ) of at least 220° about the plug-in direction, wherein the wall and/or the at least one groove is/are routed along a radial direction, perpendicular to the plug-in direction, through the rim; wherein a clearance is in each case provided along an encircling direction on both sides of the wall, between the rim and the wall.