Mass-prouced glass canning jars, also known as Mason jars after their inventor John L. Mason, Ball jars after one of the earliest manufacturers of the jars, and fruit jars because many are decorated with a fruit pattern, have been manufactured since the early 1850s. An earlier British jar is known as the Kilner jar. Mason jars are made of glass, and come in a variety of sizes including quart, pint, half-gallon, and cup sizes, as well as in wide-mouth and regular mouth shapes.