Our "Culture Tube Formicarium" uses this test tube and insert; you can swap them easily, replace a broken tube or expand your existing set. Even better, thanks to the inclusion of a cone adapter, you can use them as a stand-alone expansion to any of your existing setups, including the culture tube formicarium itself. 
 
Each tube includes a 16x125mm borosilicate test tube, a long plastic insert, a long black jacket with rings, a 1 cm silicone fitting and a plastic cone adapter for vinyl tubing of the diameter of your choice.
 
Alternatively, you can choose a plain plastic insert or one with a sanded texture.
 
The test tube measures 16x125 mm, and the insert is 115 mm long. The vinyl tubing adapter can be 9.5 mm (93/8") or 12.7 mm (1/2") in diameter.
 
 
*** Vinyl tubing not included.