✅ Perfect for Beginners and Pros: Our 4 fermentation lids fit securely to all wide mouth large mason jar. Designed with a date tracking ring, easy opening tabs, a step-by-step fermentation guide, a pump for air extraction, and pen and labels. ✅ Never Lose Track of Your Ferment: We’ve designed a built-in date tracker for every canning lids - no more writing it on paper, then losing it. We have these mason jar lids only designed specifically for fermenting, with a date tracker installed into each lid, so you know exactly when that batch is nearing the end of its fermenting cycle. You can then begin to taste it and determine if it's finished. Perfect accessories to your canning equipment. ✅ Easy Tab Handle: There is nothing more frustrating than those mason jars with lids that just won’t open. Luckily for you, our fermentation lids have incorporated an easy twist tab that ensures you have the leverage to open those hard-to-crack canning jars with ease. ✅ Air Extraction Made Easy: Using our one-way fermentation vacuum pump technology, you only have to put your pump on top and make a few movements to keep your ferment happy and healthy. Use an extractor pump to pump air out of the fermentation jar by connecting a built-in one-way valve in the middle, extruding the fermenting jar valve in the middle when fermentation finishes, and using the anti-slip release tabs at the edge to help you open the mason jar easily. ✅ Ideal for Fermented Foods and Fermented Vegetables: Whether you're into sauerkraut, pickle, kimchi, or experimenting with various fermentation recipes, our easy wide mouth mason jar preserving lids provide the ideal environment for your fermenting ventures, yielding consistent and delicious results every time.