Bubble Glass – What is it in Vaping?

Definition

Bubble glass is a bulged replacement tanksection for vape atomisers that instantly increases e-liquid capacity without altering the device’s height. Shaped like a subtle “bubble” or sphere in the middle, this glass section replaces the standard straight cylinder on sub-ohm tanks, RTAs and some pod mods. By expanding the internal volume, vapers can enjoy longer sessions and fewer refills while keeping the original compact form factor of their Mod“>box mod setup. Made from heat-resistant borosilicate or quartz glass, bubble glass is transparent so juice levels remain visible, and it resists cracking from acidic e-liquids or rapid temperature changes.

Technical Details

Bubble glass works by creating a wider central chamber between the top and bottom o-ring seals of the tank. Typical capacity jumps are 25–100 %: a 2 ml straight glass becomes 3.5–5 ml, while a 5 ml straight section can reach 7–8 ml. Wall thickness averages 1.5–2 mm to withstand vacuum pressure and minor impacts. Standard diameters match the tank base (24 mm, 26 mm, 28 mm) but flare outward to 28–32 mm at the widest point. Variants include “fat boy” ultra-bubble, “mini bubble” for stealth setups, and coloured or frosted versions for UV protection and aesthetics. Always check compatibility with coil platform and bottom coil / BVCchimney length before purchase.

Usage & Tips

• Installation: Disassemble tank, remove old glass, lubricate new o-rings with a drop of e-juice, then slide bubble glass straight down—avoid twisting to prevent seal damage.
• Leak fix: If gurgling occurs, ensure the glass is fully seated against the Deck“>build deck shoulder and that coil threads are tight; uneven pressure can break the seal.
• Safety: Inspect for micro-cracks weekly; compromised glass can shatter under vacuum when the battery fires. Carry a spare straight glass in case of drops.
• Travel: In Australia, TPD-regulated pods remain at 2 ml; bubble glass is legal for personal use but empty tanks to 2 ml when flying domestically to avoid leaks from cabin pressure.

History & Context

Bubble glass emerged around 2016 when the EU’s TPD capped tank capacity at 2 ml. Manufacturers released bulb extensions to restore practical capacity, and the design quickly became a global aftermarket staple. Today, almost every major sub-ohm tank ships with both straight and bubble glass in the box, reflecting vapers’ demand for high-capacity, pocket-friendly setups.