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DOWNSTEM FOR BONG

A bong downstem is an essential component of a water pipe or bong that connects the bowl and bong. It is a tube, usually made of glass, with diffuser slits or holes at the bottom end to help filter and diffuse the smoke.

When using a bong, the glass downstem is inserted into the water chamber, which allows the smoke to be pulled down into the water. As you inhale through the mouthpiece, the smoke will pass through the downstem and be diffused into the water. This process helps to cool and filter the smoke, providing a smoother and more enjoyable smoking experience.

Optimize your bong's performance with our precision scientific glass downstems, engineered for perfect airflow and filtration. Our collection features diffused downstems with 4-20 slit patterns that create micro-bubbles for smoother hits, alongside straight downstems for classic setups. Available in critical sizes: 14mm and 18mm joint diameters (male/female) and lengths from 3 to 8 inches to fit beaker bongs, straight tubes, and recyclers.

Each downstem is crafted from thick borosilicate glass with ground joints for airtight seals and includes measurement indicators for water level optimization. Whether you need a replacement stem or want to upgrade diffusion, our downstems reduce drag, prevent splashback, and maximize your percolator's efficiency.

Downstem Technology

Feature	Diffused Downstem	Straight Downstem
Design	Slits at bottom (4-20 cuts)	Single open end
Function	Creates micro-bubbles	Direct airflow
Best For	Smoother hits	Maximum airflow
Bong Type	Bongs without percs	Percolator bongs
Maintenance	Harder to clean (slits)	Easy cleaning

? Pro Tip: The Hybrid Solution

Our angled diffused downstems combine 45° joints with slit diffusion - perfect for beaker bong upgrades!

A downstem typically has two joints:

1.Male Joint: This is the upper joint of the downstem that inserts into the base of the water pipe (bong). The male joint is usually convex and can be straight, tapered, or angled to fit into the female joint of the bong's body.
2.Female Joint: This is the lower joint of the downstem that connects to the part with the bowl. The female joint is concave and is typically part of the bowl that receives the inserted male joint.

Using an adapter as an example:

The design of male and female joints ensures that the downstem can be properly connected to the bong and the bowl, forming a sealed system that allows the smoke to be filtered through water before being inhaled. It is important to choose a downstem that matches the size and joint type of your bong. Star is various sizes and joint angles available.

? Downstem Size Guide

? Joint Size

Measure your bong's joint:

14mm: ~0.55" diameter (common in smaller bongs)
18mm: ~0.71" diameter (standard for beakers)

Gender Matters:

Male joint → Downstem should be female
Female joint → Downstem should be male

? Length

How to measure: Insert ruler into joint until it touches bottom:

Beaker bongs: 4-7 inches
Straight tubes: 3-5 inches
Recyclers: 2-4 inches

Pro Tip: Downstem should sit 0.5-1 inch above bong bottom

How to purchase a suitable replacement downstem?

1. Downstem Length: The length of your downstem should be measured from the tip of the downstem to the end of the ground joint. To measure your pipe, we recommend inserting a pencil into the joint. Push it as far down as you would like your downstem to fit. Then, measure the pencil length from the joint to the pencil tip. See the diagram below.

2. Ensure the two joints sizes of the replacement downstem matche the sizes of your bong and your bowl. Common downstem joint sizes on the market include 10mm, 14mm, and 18mm. If your bong has a 18mm female joint and bowl has a 14mm male joint size, then you should select a downstem with a 18mm male joint and 14mm female joint size.