How to Measure Your Downstem: Easy Guide

So your downstem broke (RIP), or you're just looking to upgrade your setup. Either way, you need to measure that bad boy correctly, or you'll end up with a piece that doesn't fit. Let's make this super simple.

What's a Downstem Anyway?

A downstem is the tube connecting your bowl to your bong's water chamber. It directs smoke down into the water for filtration and cooling. According to studies on smoke filtration from various universities, water filtration removes harmful particles while cooling the smoke by up to 40%.

Why Measuring Matters?

Get the wrong size and your downstem either won't fit or won't reach the water. There are two main measurements you need: joint size and downstem length.

Step 1: Figure Out Your Joint Size

Bongs use standardized glass-on-glass joints. There are three common sizes: 10mm, 14mm, and 18mm. Here's how to measure yours:

1. Grab a dime, it's 18mm across
2. A penny is 19mm, so if your joint is smaller than a penny, you probably have 18mm
3. If a dime is too big, you likely have 14mm (the most common)
4. 10mm joints are rare and usually found on tiny rigs

You can also use a ruler to measure the outer diameter of your joint opening. Most bongs have 14mm or 18mm joints.

Step 2: Determine Male vs Female

Your bong's joint is either male or female:

1. Female joints have an opening where you insert things
2. Male joints stick out

Most bongs have female joints. Your downstem needs to match; if your bong has a female joint, you need a male downstem.

Step 3: Measure the Length

This is where people mess up. Here's the right way:

1. Measure from the bottom of the joint to where you want the downstem to end in the water
2. The downstem should sit 1-2 inches below the water surface for optimal filtration
3. Too short and you won't get proper filtration
4. Too long and it'll scrape the bottom or not fit at all

Pro tip: Downstems are measured in inches, usually ranging from 3 to 6 inches. Common sizes are 3.5", 4.5", and 5.5".

Types of Downstems

Not all downstems are the same. Here's what you can choose from:

Standard Downstems

These are basic tubes. They work fine, but don't offer extra filtration.

Diffused Downstems

These have slits or holes at the bottom. Research shows diffused downstems increase water contact by 65%, creating smoother hits by breaking smoke into smaller bubbles.

Fixed vs Removable

Some bongs have fixed downstems (welded in place). Others use removable ones that you can swap out. Removable is better for cleaning and upgrades.

Quick Shopping Tips

When buying a new downstem:

1. Look for borosilicate glass, it's heat-resistant and durable
2. Get a diffused downstem for smoother hits
3. When in doubt, go slightly shorter rather than longer
4. Check the angle; Most downstems, which sit at 45 degrees

Common Mistakes

Don't guess the size. A wrong measurement wastes money and time.

Don't forget to account for the joint itself measure from where the downstem enters the bong, not from the top of the joint.

Don't buy the cheapest option. Thin glass breaks easily. Spend a few extra bucks on quality borosilicate.

The Bottom Line

Measuring your downstem is simple: figure out your joint size (10mm, 14mm, or 18mm), determine if it's male or female, and measure the length from joint to water. A properly sized diffused downstem provides 65% better filtration compared to standard tubes.

Got your measurements? Check out DankStop's massive selection of downstems. We've got every size, style, and budget covered. No more guessing, just smooth, filtered hits every time.