The present invention relates to a fin (103) for a plate heat exchanger having an angular, wave-shaped structure with wave crests (131) arranged in parallel to one another, wherein a wave crest (131) is connected via a wave flank (132) to another wave crest (131), and wherein the wave crest (131) and the wave flank (132) succeed one another in a first spatial direction (D1), and wherein the wave crest (131) and the wave flank (132) are connected to one another by a sheet edge (134). The wave crests (131) have a flat outer surface (135). According to the invention, the outer radius (R101) of the sheet edges (134) is 0.05 mm to 0.18 mm. A method for manufacturing a fin (103) is also provided, which comprises a pressure-shaping step in which a previously provided bent wave-shaped structure (3) is shaped such that the outer radius (R1) of the sheet edges (34) is reduced (R101).