A device may include an interface to send authentication information to a plug-in, where the authentication information is related to a client device. Each seal face segment has a primary sealing surface and a section extending axially from each primary sealing surface The holder halves are adapted to be joined together to rigidly hold the circular seal face. The pump moves fluids by direct mechanical displacement from two micro-syringes arranged in parallel. The electrically conductive blade can be coupled to a shaft via at least one blade retainer. Furthermore, the transparent electrode would be arranged on the reflective layer pattern and the exposed portions of the pad electrode.