Header tank and corresponding heat exchanger

A mechanically assembled heat exchanger for a motor vehicle, comprising:

• a mechanically assembled heat-exchange core bundle, the core bundle comprising at least one row of tubes comprising a plurality of associated end tubes one at each end of the at least one row of tubes;
• and
• at least one header tank into which ends of the at least one row of tubes open, the at least one header tank comprising at least one end stop configured to:
• be positioned facing an internal surface of the end of one of the plurality of the associated end tubes, and
• collaborate with the internal surface in such a way as to prevent the one of the plurality of associated end tubes from moving in a direction of an interior volume of the at least one header tank,
• wherein the at least one header tank is configured to accept ends of the plurality of the associated end tubes having two opposite long edges,
• wherein the at least one end stop is configured to collaborate with at least one long edge of the ends of the plurality of the associated end tubes, and
• wherein a body of the at least one end stop comprises two concave opposite edges with their concavity horizontally oriented toward an inside of the at least one end stop.