What is a bi-stable cut?

A bi-stable cut (also called a “bi-stable cut”) is a special type of cut on glass bongs that provides more stability and robustness – especially in the area of ​​the chillum or the plug-in system.

Structure and special features
With a classic standard joint (e.g., NS 18.8 or NS 14.5), the glass of the chillum meets the bong opening directly. With a bi-stable joint, however, the transition area is reinforced: The joint is thicker and slightly conical, making it more robust and less prone to breakage—especially with frequent use or when removing the bowl.

Advantages of the bi-stable cut
More stability: Ideal for thick-walled bongs or frequent users.

Less glass breakage: The reinforced ground edge protects against chipping.

Better fit: Many users find the chillum to fit more snugly.

Longer lifespan: A quality feature, especially for high-quality bongs.

How do I recognize a bi-stable cut?
A typical feature is the pronounced bulge or ring around the joint of the bong – exactly where the chillum is inserted. This makes the joint itself appear wider and more solid than on a standard model.

A bi-stable joint can, for example, be marked with “NS 18.8 bi-stable” – important for the purchase of spare parts.