Easy to Use ---- Easy to assemble all the parts, put the silicon ring under lid and insert airlock into lid hole, then screw mason jar lid on your wide mouth mason jar. After fermentation, take off the airlock, close the silicon cap and store your fermented food on right placeEasy to Clean ---- All parts are removable, BPA FREE and food-grade material, dishwasher safe. DO NOT sterilizing the plastic airlocks with boiling waterKit Include ---- 4 BPA FREE airlocks; 4 plastic wide mouth lids with silicon rings and 4 food grade silicon grommets inside lips,extra 2 silicon ring and grommets compatible replacement.Extra silicone grommets ---- The set include extra silicone grommets.Canning Lids Fits Any Wide Mouth Jar ---- Can be used compatible Bernardin, Kerr, Ball. Any brand of "Wide Mouth" Mason jar in pint, quart, or half-gallon.