A heat dissipation device includes a first heat sink and a second heat sink juxtaposed with the first heat sink. The first heat sink includes a first base and a plurality of first fin extending from the first base with a plurality of first channels defined therebetween. The second heat sink includes a second base and a plurality of second fins extending from the second base with a plurality of second channels defined therebetween. The second fins extend beyond a common edge of the first base and the second base to extend into first channels of the first heat sink.