Basic Guide on Glass Joint Sizes
Buying a new bowl, downstem, or nail? You need to know your joint size and gender first. Here's a simple guide.
What Is a Glass Joint?
A "joint" in the glass world (different from a rolled joint) is the point where two glass pieces connect — such as where a bowl connects to a bong, or where a nail connects to a dab rig. Joints come in specific sizes and genders. Buying a mismatched piece is one of the most common and frustrating mistakes in glass shopping.
Joint Sizes: 10mm, 14mm, and 18mm
Joint sizes refer to the inner diameter of the female joint (or outer diameter of the male joint). The three standard sizes are:
10mm
- Small, compact size
- Found on mini bongs, micro dab rigs, and small pieces
- Best for small dabs and low-volume use
- Bangers, bowls, and tools must all be 10mm to fit
14mm
- The most common size across the industry
- Found on the vast majority of mid-size bongs, dab rigs, and water pipes
- When in doubt, measure — many pieces are 14mm
- Widest accessory selection available at this size
18mm
- Large diameter, used in big bongs and high-flow pieces
- Best for large water pipes and high-volume use
- Less common in smaller, portable pieces
Male vs Female Joints
Female joint: Has an opening that accepts a male piece inserted into it. Most bongs have female joints — the bowl or nail slides inside.
Male joint: A protruding piece that inserts into a female joint. Less common in bongs but standard for certain rigs and accessories.
How to Measure Your Joint
- Use a ruler or bring your piece into the store
- Measure the inner opening diameter of the joint
- Check if your bowl/nail slides in (female) or over (male) the joint
- 10mm: roughly the diameter of a pencil
- 14mm: roughly the diameter of a dime
- 18mm: roughly the diameter of a nickel
Bring your piece to Smoke Liquor 247 and our staff will measure it and find the exact fitting bowl, nail, or downstem for you. Call ahead: (407) 778-1326 (24/7).