I am new to this forum, I am a common canner/preserver who comes upon unusual jars on occasion. I have 20 jars which hold 2 3/4 cups of liquid. They have the words Ball refrigerator and freezer jar on the front and are as tall as a Quart Jar. I am unsure if I can pressure can using this jar or if I can only cold pack them. If not I may keep them as collectors. This jar is straight on the sides and has a wide mouth.