Assembly of the crystallization device for launch. (a) The JCB consists of six capillaries in a syringe case. Capillaries containing protein solutions are plugged with agarose gel and inserted into tubes, or cells, containing crystallization solutions. (b) To save space, two JCBs are coupled, i.e. the capillaries of two JCBs are positioned to fit between the slots of each other and they are put in a tray. (c) Four trays are stacked creating a JCB unit and wrapped in an inner bag and an outer bag. (d) A metallic holder contains one JCB unit. The scale bars correspond to 10 mm.