In comparison with the majority of acrylic bongs premium bongs made from borosilicate or Duran glass offer a couple of advantages. They are easy to clean, they show extraordinary craftsmanship and their smoking performance is outstanding. In addition, glass bongs are available in standard sizes, which is not always the case with acrylic bongs.
Usually the bongs have a volume of 500ml or 1,000ml. If you prefer smaller pipes then you can choose between several models with a volume of 250ml. But you can also find really bulky glass bongs with a 2,000ml volume, for which experience and a good smoke tolerance are rather advisable.
Some manufacturers do not stick to these standard sizes. Low-cost models in particular have a rather random capacity.
The joint sizes for downpipes or bowls are standardized too. In most cases the joint sizes are either 14.5mm or 18.8mm in diameter. Smaller glass bongs with less volume usually have a joint size of 14.5mm (in rare cases also 12.5mm) and the larger ones 18.8mm. But there is no general rule. The huge, bulky smoking equipments with 2,000ml volume often have a joint size of 29.2mm for a better draft of the pipe.
If you need to replace downpipes, diffuser or bowl pay attention the the right joint size.
There is a lot of equipment available for glass bongs. The most common are: