The invention relates to an arrangement which is used to secure a first heat exchanger to a second heat exchanger. The first heat exchanger (11) is arranged parallel to the second heat exchanger (1) and comprises a heat exchanger block (12) in addition to collector pipes arranged on both sides thereof, and which more particularly comprise an integrated collector (14). The second heat exchanger comprises a pipe/rib block provided with collector boxes (4) which are secured on both sides thereon and which are made of a casting or injection type material, especially plastic. The invention also relates to a first heat exchanger (11) which is secured by means of retaining means (16, 18) which are injected onto the collector boxes (4) of the second heat exchanger.