Glass Thickness:
9mm walls, 15mm base
This is heavy duty glass that won't break easily
Think of it like the difference between a regular drinking glass and a thick mason jar
The extra-thick base (15mm) adds stability so it won't tip over easily
 
Height:
18 inches (about 1.5 feet)
This is a medium to large-sized bong
Taller bongs cool the smoke more, making it smoother to inhale
 
Joint Size:
19mm Female
This is where you insert the bowl/downstem (the "female" part means it receives the piece)
19mm is a standard size, so replacement parts and accessories are easy to find
It's big enough for good airflow but not oversized
 
Tube Diameter:
50mm
This is the width of the tube and mouthpiece
Standard comfortable size - not too narrow, not too wide
 
Downstem Length:
5.75 inches
The downstem is the tube that goes from the joint down into the water
This length is proportional to the bong's height
Important if you ever need to buy a replacement - keep this measurement handy!