Food Grade Glass: Our Fermentation Weights are made of 100% food-grade glass,Lead-free,safe and and non-porous and never absorbs food odors,flavors, or colors.The ideal weight and dimension suitable for wide mouth mason jar (pint, quart, ½ gallon, etc). Clover Grip Handle:Nonslip Clover grip design make it easy to put these weights in and out of your mason jars. If the weights are too deep in the jar, it can be easily picked up with a clamp, and also can prevents saltwater splashing. Large and heavy enough to keep vegetables submerged below brine—better than DIY weights effective than DIY weights.It’s convenient for both dishwasher cleaning and hand washing. Suitable for Wide Mouth Mason Jars - With 2.7" diameter compatible Ball Jars and other brand of wide-mouth mason jars.Great for fermenting vegetables and probiotic food,small batch sauerkraut, pickles,Kimchi, and any vegetable and fruit ferments foods kit. Flat Bottom:The bottom is flat to prevent air bubbles forming underneath and prevent spoiling caused by excess oxygen.