What size bong bowl do I need?

Joint size: measure the stem’s outer edge, then round to the nearest standard size.
Joint gender: male connects on the outside, female on the inside. Match opposite genders.
Joint angle: some adapters set a 45° or 90° fit.

You need a bong bowl that matches your bong’s joint size: 10mm, 14mm or 18mm. Start with 14mm, because it is the most common. Then confirm the gender. A male bowl goes into a female joint, and same-gender joints won’t seal properly.

What’s the difference between a 14mm and an 18mm bong bowl?

The difference between a 14mm and an 18mm bong bowl is the width of the stem that slides into the joint. A 14mm bowl sits loose in an 18mm joint, and an 18mm bowl won’t go into a 14mm joint. An adapter or a reducer downstem bridges the gap.

How do I replace a bong bowl?

To replace a bong bowl, measure the outer edge of your old bowl’s stem and round to the nearest standard size. Next, note whether the stem is male or female. Then pick a new bowl with the same size and gender, so it fits your joint the same way.

What does a bong adapter do?

A bong adapter lets a bowl or attachment fit a joint it would not fit on its own. Adapters can change the joint size, switch the joint gender or adjust the angle. Common styles in this collection include male-to-male adapters, 90° step-up adapters and dropdown adapters.

How do I pick a downstem for my bong?

To pick a downstem, match three things: joint size, length and tip style. Measure from the joint opening to just above the base, and choose a stem no longer than that. Slitted or diffused tips split smoke into smaller bubbles. The downstem measuring guide linked above covers each step.