have a circular outer shape as shown in fig5 a d or a square outer shape as shown in fig5 f in the illustrated embodiments the anterior surface 112 can have a display screen 113 for displaying messages and or physiological parameters for the patient and or care providers as shown in fig2 a the posterior surface 114 of the monitor instrument 110 can include a cover 116 having a group of pogo pin holes one end of a plurality of pogo pins 117 can protrude from the pogo pin holes of the cover 116 another end of the pogo pins can form an electrical connection with the pcb inside the monitor instrument 110 to establish an electrical connection between the pcb inside the monitor instrument 110 and one or more sensors which will be described in more details below more details of the pogo pins are described in u s application ser no 15 017 349 referenced above in the illustrated embodiment the plurality of pogo pins 117 is arranged in two rows a person of ordinary skill in the art will appreciate from the disclosure herein that the configuration of the plurality of pogo pins is not limiting additionally although fig2 a shows one cover 116 with a plurality of pogo pins 117 in a center.