Printed Parts: The main otoscope body weights 20 grams. The battery cover weights 6 grams. The switch cover weights 2 grams. The circular base on which the lens assembly and the speculum mounts weights 5 grams. The ear piece weights 3 grams. The lens assembly weights 3 grams. Other Parts: A SMD pushbutton switch is used to activate the otoscope's light. The approximate cost of this part is $0.57. A white LED is used to shine light into the ear. A 220 ohm resistor is used to limit current draw. A 38mm diameter, 150mm focal length concave lens in used. About half a meter of 22 gauge solid core wire is used.