The invention relates to an apparatus (10) for the thermal treatment of metallic products, which comprises (a) a support and transport plane (24); (b) at least one collector module (12) comprising at least one collector (14, 16), the collector (14) being provided with a perforated plate (22) facing the support and transport plane (24); (b-2) a conduit (20) connected to said at least one collector (14), and (b-3) integrated in said conduit (20), at least one stop valve (18). The stop valve (18) is situated at a distance from the collector (14) which does not exceed 60 cm. The perforated plate (22) is provided with holes which are arranged in rows parallel to each other but not in parallel rows with respect to the sides of said perforated plate. The rows are inclined with respect to two opposite sides of the plate (22) of an acute angle.