Abstract: A honeycomb body, in particular for a catalytic reactor for exhaust gases of an internal combustion engine of a motor vehicle, has passages through which a fluid can pass from one end to the other and structured, or smooth and structured, sheet metal layers. At least a part of the sheet metal layers has a thickness of less than 40.mu., preferably about 30.mu., and at least a part of the sheet metal layers with a thickness of less than 40.mu. has portions with additional reinforcing structures. The additional reinforcing structures are preferably bent-over portions in the region of one or both ends of the honeycomb body, in particular to a depth of from 1 to 10 mm, preferably about 3 to 5 mm, from the ends. The sheet metal layers can be joined together by brazing at least at a part of their contact locations, more particularly preferably in the regions of the additional reinforcing structures.