Holding device

The invention relates to a holding device on portable boxes such as coolers, for fixing on car seats. For this purpose, it is provided to arrange at least one guide device with an insertion opening for a flat band, a safety belt, or a pull strap on the lower part and/or the upper cover part of the box. The clear width of the insertion opening is matched to the band thickness of the flat band, safety belt, or pull strap, whereby the guide device furthermore has a relatively flat receiving area with a width of at least the width of the flat band, the safety belt, or the pull strap.