Abstract: An assembly for electroless metallization of a target surface (11) of at least one workpiece (10), comprising—a container (13) for receiving an electrolyte solution—an inlet for the electrolyte solution, said inlet arranged in the base (15) of the container (13), wherein the inlet (20) is designed as an inlet port (21) with a diffuser plate (24) comprising inlet openings (25) arranged in concentric circles—an outlet (30) which is arranged on an upper side of the container (13)—a receiving area for holding the at least one workpiece (10), wherein the diffuser plate (24) is formed as a first assembly (31) and a second assembly (32), which is identical to the first assembly, of a respective plurality of inlet openings (25), wherein the assemblies at least partially but not completely overlap, and the inlet (20) has at least two inlet ports (21, 22).