This is a very useful piece of kit. It slips into any 18mm bowl slot, and reduces it to 14mm, letting you use all you 14mm kit on any 18mm piece. It goes by many names: adapter, reducer, interchanger, 18 to 14 converter and probably many more.
GOG ADAPTER 18 to 14
This is an 18mm to 14mm adapter.
QI Bong to Rig 14mm
This is a 2.5 inch 14mm female to female adapter.
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