An iodine tube or a kit for detecting fingerprints with iodine vapor is a convenient tool for quickly detecting sweat and grease fingerprints on various porous surfaces (paper, cardboard, plywood, porcelain, tiles, plastics, etc.). It is not recommended to treat metal objects with iodine vapor, as iodine can cause corrosion. A distinctive feature of this method is the instant detection of the trace, unlike other methods - ninhydrin, DFO, etc. The disadvantage of this method is the short-term detection of the trace. After detection, the trace remains for 5-15 minutes. In this case, the trace can be fumigated many times.