This 18mm male to 18mm female diffused downstem is a wonderful choice for a female-jointed water pipe or dab rig. For those who appreciate thorough filtration with their glass piece, this 6-slitted downstem is exactly the kind of accessory vyou're looking for.
Regarding the varying lengths of the 18mm to 18mm Diffused Downstem, the length is measured from above the ground joint to the bottom of the stem. Check out the measurement guide, within the product photos, for a great visualization.
CLEAR GLASS: This piece features sleek and clean clear glass that allows you to watch this concentrate rig or water pipe function. Clear glass allows you to watch the bubbles stack as your smoke/vapor percolates
18MM JOINT: This item features an 18mm joint size. It will fit other 18mm pipes/accessories of the opposite gender.
MALE JOINT: This item features a male joint. It will fit all female jointed pipes and accessories of the same size.