What’s the Arizer Solo Stem Diameter?

If you’re shopping for accessories or trying to DIY a stem solution for your Arizer Solo, Solo 2, or Air series vaporizer, stem diameter matters—a lot. Whether you’re making your own holder, looking for compatible parts, or just trying to understand how it fits into your setup, here’s a clear breakdown of the Arizer Solo stem dimensions.

Quick Answer: Arizer Solo Stem Diameter

The standard Arizer Solo glass stem has a diameter of approximately 14.75mm at the herb-loading end (the part that fits into the device) and 12mm at the mouthpiece end. This slight taper helps form a snug seal with the vaporizer's heater and allows for easy, comfortable inhalation.

Why Diameter Matters

• Device Compatibility: The 14.75mm end is designed to sit securely in the Solo, Solo II, Solo III, Air, and Air Max devices without the need for additional seals or adapters. In fact they fit all Solo and Air models. 
• Airflow Control: The narrow 12mm mouthpiece end helps maintain vapor pressure and smooth draw resistance.
• Accessory Fit: Many third-party accessories (like cooling stems, bubblers, or adapters) are designed to match these specific dimensions for a proper fit.

Measuring Your Stem

If you're trying to replace a broken stem or want to ensure a third-party option will fit, use a digital caliper for accuracy. Keep in mind:

• 14.75mm is the outer diameter at the heater-end (goes into the device)
• 12mm is the outer diameter at the mouth-end (you inhale from here)

What About Water Pipe Compatibility?

Since the stem’s heater end is close to 14.75mm, it doesn't directly fit most 14mm or 18mm water pipe joints without an adapter. If you're planning to use your Solo with a water piece, look for Arizer-to-14mm adapters designed specifically for this purpose. These are typically ground glass adapters that hold the stem securely in place.

Learn more about how to use your Arizer Solo with a bong here. 

Looking for a Replacement or Upgrade?

At The Vapetrix, we offer a curated selection of premium Arizer Solo stems—including cooling stems, colored glass options, and 3D diffusers—each designed to the correct 14.75mm base and 12mm tip diameter for perfect compatibility.

Final Thoughts

The Arizer Solo’s stem size—14.75mm at the bottom and 12mm at the top—may seem like a small detail, but it’s critical to performance and compatibility. Whether you’re replacing a broken stem or shopping for new upgrades, make sure those dimensions match.

Need a new stem? Check out our post comparing the Arizer Evolution Cooling Stem VS The Vapetrix Cooling Balls Stem!