Why Choice Handheldvac Lids for Food Fermentation? Handheldvac fermenting Lids are perfect for all levels of fermenter, and the operation is also very simple. The lids are designed with a One-way valve structure, the air inside the jar can be exhausted, while the air outside the jar cannot enter the jar. When we ferment food, the gas CO2 created by the bacteria will push the oxygen out of the jar, and keep oxygen from entering our fermentation. If you want to keep your food fresh longer, we can use the air pump to pull the oxygen out of the jar. ● Specially designed of one-way valve structure ● Strong vacuum sealing creates an air-tight barrier ● Simple operation are perfect for all levels of fermenter ● Reusable and resealable for frequently used food items Why Use Split-type Design? When we need to open the lid,due to the long-term processing of the sealed state, the traditional of integrated lid will be difficult to open lid, but we use this split-type , there is no such problem. It contains two parts, one is a band, another is a lid, the band enhances the lid seal. and easy to remove from the jar. Compatiable with Many Vacuum Tools Manual Vacuum Pump Handheld Electric Pump Vacuum Sealer machine The handheldvac brand was founded in 2016. The inspiration of the brand comes from the designer's re-excavation and upgrading of kitchen life and the home environment, aiming to create a new kitchen and better life. The handheldvac brand adheres to the business philosophy of healthy, recyclable and sustainable development. The products are favored by consumers for their convenience and practicality. Handheldvac Mason Jar Vacuum Lids Keep Food Fresh for Longer Mason Jar Vacuum Lids compatible with many vacuum tools, such as manual vacuum pump, mini electric pump, vacuum sealer machine,and the compatibility of multiple ports can reduce costs. Strong vacuum seal, can effectively prevent outside air from entering the jar, it is very beneficial for long-tem preservation of food. Reusable feature can save your money. Simple operation, won't bring you any trouble. ● Specially design ● Strong vacuum sealing ● Simple Operation&Reusable ● Compatiable Interface Step1 How to use food vacuum lid Place the lid over the mason jar and use the vacuum pump to exhaust air from the mason jar. (At this point, we can judge the vacuum is well pumped by whether the lid is loose) Step 2 Screw band down tightly on the lid, keeps lid for a stronger seal. Step1 How to release vacuum lid Release the vacuum by pressing on the side of the valve with your finger. If you don't hear a hissing sound, press at a new point 90 degrees away from the first point. Step 2 Screw the lid off the mason jar