Help us help you… use this handy guide to help you measure your glass on glass joints!  The most common joint sizes are 10mm, 14mm, and 18mm… these can be male or female.  Since we have a no return policy on merchandise, it’s best to make sure you are asking for the correct size of replacement down stems, bowl slides, bangers, ash catchers, etc.  Use a standard USA penny to find out what size and sex your piece needs!