The origin and use of this type of folding knives is not very clear and there are numerous suggestions. We think that they are used by opium smokers to clean their pipes, and for that purpose they are perfectly designed. Their origin is most probably from the Indo-China area. Both knives are similar but differ in materials. The bigger one has a 4 ½ inches blade, 4 inches back spike and horn handle. 7 ½ inches fully opened. The smaller knife is 3 ½ inches blade, 3 inches spike and 6 inches fully opened. It has a silver inlaid inscription on the blade and ivory handle with nice shining age patina. Both in very good condition and only a small nick to the edge.