Fermentation, Fermenting Glass Jar Weights 4 Pack 2 1/2" to Fit a Wide Mouth Quart Jar Made in the USA! Not china. Lead free Glass. Bpa free These have a slight green color to them because of the type of glass used (Soda-lime glass) It measures 2 1/2", and 3/8" thich Fit a wide mouth quart jar