In a flame arrester insert comprising two metal strips (1, 2) wound together, of which a first metal strip (1) is a smooth strip and the second metal strip (2) is a grooved strip having defined grooving, so that they rest on each other at defined contact points (3) and, between the contact points (3), form defined gaps (4) for the passage of a fluid, the stability can be increased and corrosion prevention can be implemented even with inexpensive materials by the metal strips (1, 2) resting directly on each other at the contact points (3) and, outside the contact points (3), having a surface coating (5) which, close to the contact points, is a uniform joint coating of the surfaces of the metal strips (1, 2) that point toward each other.