Geekvape Z Max Tank 4ml Bubble Glass

A Pyrex bubble glass replacement for the Geekvape Z Max Sub-Ohm Tank. Capacity: 4ml in the expanded bubble profile. One glass per pack. This is the part you need when your Z Max glass cracks, chips, or you just want the extra capacity that the bubble shape gives over the standard straight glass section.

Fits the Z Max DTL Tank only. Not the Z Nano, not the Z Sub-Ohm (older model), not the Zeus range. The Z Max specifically. If you are not sure which tank you have, check the base of the tank body for the engraved model name before ordering.

Why vapers choose this:

• 4ml capacity instead of the stock 2ml, which roughly doubles the time between refills during a heavy vaping session

• Genuine Geekvape Pyrex built to the same heat tolerance as the glass that ships with the tank

• Bubble profile adds width at the midsection without changing the base or top diameter, so it drops straight into the existing O-ring seals

• Under three quid and it prevents you from replacing an entire tank when the glass is the only damaged part

Geekvape Z Max Bubble Glass Features

Why the Bubble Shape Matters at High Wattage

Running the Z Max at 50W to 80W with a sub-ohm mesh coil burns through liquid quickly. The standard 2ml straight glass means refilling every 20 to 30 minutes for heavy vapers. The 4ml bubble glass gives you roughly twice that window. It does not change the airflow, the coil compatibility, or the drip tip fitment. It just holds more liquid between the same O-rings.

Pyrex, Not Soda-Lime

Geekvape uses Pyrex (borosilicate) glass for the Z Max rather than cheaper soda-lime glass. The difference is thermal shock resistance. Pouring cold liquid into a tank running warm coils at 60W+ can crack low-grade glass. Pyrex handles that temperature shift without stress fractures. If you have ever had a glass crack seemingly on its own after a refill, cheap replacement glass was probably the cause.

Do Not Confuse Z Max with Z Sub-Ohm

This is specific to the Z Max tank. Geekvape's Z series includes several tanks with similar names: the Z Sub-Ohm, the Z Nano, the Zeus X, and the Zeus Sub-Ohm. Each has a different glass diameter and profile. The Z Max glass will not seat properly in any other tank from the range. Check the engraving on your tank base before ordering.

Bubble Does Not Mean Fragile

The wider midsection on bubble glass looks more exposed than a straight tube, and people worry about that. Fair enough. But the Pyrex wall thickness is the same, and the O-ring seals at both ends hold it in place identically to the straight version. The bubble shape does sit slightly wider in the hand, which is worth knowing if your tank sits in a tight mod sleeve or carry case.

How to Replace the Z Max Bubble Glass

Quick swap. Two minutes, no tools.

1. Empty the tank of any remaining e-liquid. Pour it out or vape it down. Do not attempt to swap glass with liquid still inside.

2. Unscrew the base of the Z Max tank from the chimney section. The glass, coil, and base will separate from the top cap.

3. Slide the old glass off carefully. If it is cracked, wrap it in tissue first to catch any fragments. The glass sits between two O-rings and should slide free with gentle pressure.

4. Slide the new bubble glass on, seating it over the lower O-ring first, then aligning the top. You will feel it sit snugly when both O-rings grip.

5. Screw the base back on finger-tight. Fill with your chosen e-liquid, wait a couple of minutes for the coil to saturate if it is fresh, and you are set.

What's in the Box

One Geekvape Z Max 4ml bubble glass. That is the entire contents. No O-rings, no coil, no tank, no drip tip. If your O-rings are worn or damaged, order replacements separately from the Vape Accessories section.

The Right Glass for the Z Max, Nothing Else

This glass fits the Geekvape Z Max Sub-Ohm Tank and nothing else in the Geekvape Range. The Z Max uses Geekvape's own mesh coil system, and if you are replacing the glass, it is worth checking the condition of your Geekvape Coils at the same time.

A cracked glass often means liquid has leaked onto the mod connection, and a fresh coil eliminates the risk of a compromised seal causing further issues.

About Geekvape

Geekvape's Z series tanks are among the most widely used sub-ohm tanks in UK vaping. The Z Max sits at the top of the range with the largest coil compatibility and highest airflow throughput. Geekvape is known for building tanks and mods that take a beating, and the Aegis line in particular has set a benchmark for durability in the mod market.

The Z Max inherits that engineering philosophy: stainless steel construction, leak-resistant top-fill, and genuine Pyrex glass. Replacement parts like the bubble glass are manufactured to the same spec as the originals that ship with the tank.

Stock Up and Save

Glass breaks. Not always, but often enough that keeping a spare in a drawer saves you from a week without your tank while you wait for delivery. Grabbing two at this price costs less than a single refill bottle and means you are covered if the worst happens.

Every order from Pirate Vapes ships same day before 4 pm. Over 18s only. Age-verified checkout. Free Pirate Post on orders over £25. Pirate Vapes stocks genuine Geekvape parts, so you are getting the same glass that ships with the tank.

Conclusion

The Z Max bubble glass does one job: it replaces the glass section on your Geekvape Z Max tank and doubles the liquid capacity from 2ml to 4ml. Genuine Pyrex, correct fitment, and a bubble profile that drops into the existing O-ring seals without modification.

If your glass is cracked or you simply want fewer refills during a DTL session, this is the part you need. Browse more from the Replacement Tank Glass collection at Pirate Vapes.

FAQs

Does this fit the Geekvape Z Sub-Ohm Tank?

No. The Z Max and Z Sub-Ohm are different tanks with different glass diameters. This glass is for the Z Max only. Check the model engraving on your tank base before ordering.

What capacity does the bubble glass give?

4ml. The standard straight glass that ships with the Z Max in the UK holds 2ml. The bubble shape adds the extra volume through a wider midsection.

Is this Pyrex or regular glass?

Pyrex (borosilicate). It handles temperature changes better than soda-lime glass, which is the cheaper alternative some third-party replacements use.

Do I need new O-rings when I swap the glass?

Not usually. The existing O-rings on the Z Max should grip the bubble glass the same way they grip the straight version. If either O-ring is visibly worn, cracked, or no longer seating tightly, replace it before installing the new glass.

Will the bubble glass change my airflow or coil compatibility?

No. The base and top cap fitment is identical. The only difference is the wider midsection that holds more liquid. Airflow, coil type, and drip tip all remain exactly the same.