The design of a conventional syringe includes a dead space between the needle and barrel of the syringe called the hub. Syringe hub collects liquid that once drawn up, cannot be plunged out. As a result, the substance remaining in the hub is inevitably wasted and difficult to account for.
The syringe cap, syringe cover is used to make syringe prefilling programs safe, designed to guard the tip of the syringe from touch contamination.