The Silicone Hammer Style Bubbler. While the entire body of the bubbler is made of silicone, there is an inlaid borosilicate glass container for dry herbs. This way, you don't expose the silicone directly to the flame when using the bubbler. Just be careful with the flame, making sure it doesn't come into contact with the body of the bubbler. The silicone hammer style bubbler uses a removable stem for filtration.