Fixing device

The attachment device has at least one holding spring (2) for attachment to a side wall (1) of a housing of the fitted device that protrudes out of the housing at least partly transversely to the fitting direction (5). The spring is yielding in the direction of the housing and can be locked to the side wall in one of several positions along the fitting direction. The side wall has at least one row of several locking openings (4-4'') of identical cross-section arranged in series in the fitting direction and the holding spring has at least one latching fitting (8) for engagement with the locking openings.