Johnny ball style porcelain strains. Pastel pink, green, and blue. Made by Koransha in Arita, Japan. These are part of a set of around 14 different colors. I have a red and a cobalt on the way. These are fairly new and not produced anymore. Very limited production. Although they are insulators they were sold as hand warmers or paperweights. Nice size, about 3 inches long. Koransha has made insulators in the past, I have seen a few old strains with this marking, military type rod strains from the WW2 era in Europe. Very old company, mostly producing artistic porcelain ware now.