Most bongs out there use a glass on glass joint (also known as glass joint). The only other mechanism is a slide which uses a robber grommet and a thin glass tube that ‘slides’ through the grommet (our plastic bongs nearly always use this method). The diameter on a standard slide is made as a single size, so sizing for these is not an issue. However, glass joints are not as straight forward.

There are 4 different sizes of glass joints that we stock here at HerbTools and they are all measured in millimetres. They are as follows; 10, 14.5, 18.8 & 29.2 mm.

Knowing the joint size of your bong comes in very handy when looking to replace the downstem and bowl (or making bong modifications). At HerbTools all of our our glass bongs have the joint size listed on the product page, but if you need some advice you can always contact us for help.

Identifying your bongs Joint Size

If you do not know the size of your bongs joint, you can simply measure it for yourself using a tape measure or ruler. Measure the internal width of the open socket at the widest point, as seen in the picture above. So if your bong joint measures up at 14.5mm, you will need a 14.5mm downstem.

Here is a little bit of extra information…

Male & Female Joints

A male joint has an insert, while a female joint has a socket. The male is inserted into the female, that should be pretty easy to remember!

Most bongs have a female joint, which means they require a male downstem and bowl. So if your bong joint measures up at 14.5mm, you will need a 14.5mm downstem.

Did you know that we sell some incredible bongs right here at HerbTools? Check out all our cool smoking products and get your order delivered the very next day!


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