What are the plug-offs made of?

There are three different types of locking plugs:

1. Black blocker plugs are included as standard with all Berkey Light water filters and some stainless steel models. The black plugs are made of FDA-approved Buna rubber.
2. Off-white stopper plugs (rubber cork) are available for the Berkey Light models and some stainless steel models. The off-white plugs are made of food-grade M18 pure natural rubber.
3. White locking plugs (bolt and nut) are used in some stainless steel models. They come with a nut, a screw, and two transparent rings. The nut and screw are made of polypropylene. The rings are made of food-grade silicone.

Please note that the water in the lower chamber of your water filter will not come into contact with any of the plugs. This is because the water is filtered before it reaches the lower chamber.