Downstems

What is a Bong Downstem?

A downstem is the glass connector that carries smoke from the bowl into the bong’s water chamber. This is the first stage of cooling and filtration. At the bottom, most downstems have slits or holes (diffusers) that create bubbles, starting the filtration process before the smoke even hits your lungs. Without it, your bong is basically just a vase.

The Essential Guide to Downstem Sizing

Getting the right size is the difference between smooth sessions and wasted money. Here’s how to nail it:

1. Joint Size – This is the diameter of your bong’s opening. Standard sizes are 10mm (small), 14mm (medium), and 18mm (large). Your downstem must match.
   
2. Length – Stick a pencil in your bong’s joint until it touches the base. Mark it at the joint’s top, then measure. That’s your downstem length. Length is always measured from the top of the frosted joint to the very end of the tip.
   
3. Joint Gender – Most bongs have a female joint, so you’ll usually need a male downstem. Double check your piece before you buy.
   
   

Pro tip: Too short and it won’t reach the water. Too long and it won’t fit. Get it right, and you’ll never stress about compatibility again.

Upgrade Your Hit: Diffused vs. Perc Downstems

Not all downstems are created equal:

• Diffused Downstems – Basic, reliable, and effective. Slits at the bottom create bubbles for simple cooling.
  
• Percolator Downstems – Built for smoother sessions. Designs like showerhead or tree perc create a storm of tiny bubbles for enhanced filtration before the smoke even reaches the bong’s chamber..
  

Think of diffused as the “standard issue” and perc downstems as the “tech upgrade” for exceptionally smooth hits.

From Our Community

“Bought this for a friend who always breaks glass. It works surprisingly well and the slide doesn’t get stuck like glass-on-glass. Ended up grabbing one for myself too.”
— Verified Customer Review