A search in this forum and on Google has netting no information on Safe Seal jars. I have 3, all aqua, but different. One is a tall half gallon with a bail top, #4 on bottom, patent 7/14/1906. The two pint ones have the bail, one with the underscored #8 on the bottom and the other with a symbol that looks like a strange letter "p," or the musical symbol for a sharp(?) note. All have a big circle on the bottom. Thanks for your knowledge. Rosanna