Where theÊ18mm to 14mm Vertical Cut Downstem differs from a standard glass downstem are the cuts. Instead of having multiple slits running perpendicular around the downstem, the vertical cuts run parallel. The bottom of the downstem is also closed off, so the diffusion will only occur within the vertical cuts. Test out different cuts in our downstem section to see which style you like best. TheÊ18mm to 14mm Vertical Cut Downstem comes in many lengths to fit your bong perfectly. Use our measuring guide if you are not entirely sure what size you need.