not shown is pushed onto the other connector leg this presses the stop element 19 with its shoulder downwards into the recess 26 and then stops with its end face at the first hollow section 2 consequently a tight and essentially gap free connection of the hollow sections 2 can be formed the plug in connector 1 may have a receiver 12 for a sealant 13 in the area of the connection point 8 the sealant 13 may have a different consistency and shape it may consist e g of a plastic butyl compound as an alternative as an elastically shapable sealing pad it may consist of a foam plastic or the like the sealant 13 may be applied to the connector 1 by the manufacturer as an alternative it may be applied or filled in at a later date and especially during the plugging in of the hollow sections 2 in a one part plug in connector 1 not shown the receiver 12 may for example be formed by a shortened roof wall which extends transversely between the side walls 15 16 in a multipart plug in connector 1 the inner part 3 may have a trough shaped depression at its middle wall 10 pointing outwards which depression forms the receiver 12 for the sealant 13 as shown in the embodiment the receiver 12 may extend on both sides up to the external side walls 15 16 the receiver 12 and the sealant 13 lie at the level of the center stop 18 and of the recess 26 at least in terms of area fig7 illustrates this embodiment consequently the sealant 13 can penetrate the recess 26 at least in.