An electrical connector system suitable for electrically connecting a first electrode to a second electrode printed onto a substrate, the system comprising: a male connector comprising the first electrode located proximal to a first end of the male connector; and a female connector comprising: a coupling portion forming a cavity with an opening into which the first end of the male connector may be received, the coupling portion having one or more biasing surfaces that each oppose a base of the female connector; and a housing formed by sidewalls and a rear wall into which the male connector is to be received, wherein: the rear wall opposes the coupling portion; and each side wall is connected to the rear wall at corresponding corners; wherein the electrical connector system is configured such that when the male connector is urged into the coupling portion, the first electrode is urged towards the base of the female connector by the one or more biasing surfaces to form an electrical connection between the first electrode and the second electrode positioned between the base and the first end of the male connector; wherein the system is configured such that the first electrode is urged towards the base of the female connector in response to the first end of the male connector being inserted into the coupling portion at an angle to the base of the female connector and being rotated towards the base of the female connector; characterized in that: a distance between the coupling portion and the rear wall is substantially the same as a length of the male connector from the first end of the male connector to a second end of the male connector that is opposite to the first end. a male connector comprising the first electrode located proximal to a first end of the male connector; and a female connector comprising: a coupling portion forming a cavity with an opening into which the first end of the male connector may be received, the coupling portion having one or more biasing surfaces that each oppose a base of the female connector; and a housing formed by sidewalls and a rear wall into which the male connector is to be received, wherein: the rear wall opposes the coupling portion; and each side wall is connected to the rear wall at corresponding corners; a coupling portion forming a cavity with an opening into which the first end of the male connector may be received, the coupling portion having one or more biasing surfaces that each oppose a base of the female connector; and a housing formed by sidewalls and a rear wall into which the male connector is to be received, wherein: the rear wall opposes the coupling portion; and each side wall is connected to the rear wall at corresponding corners; the rear wall opposes the coupling portion; and each side wall is connected to the rear wall at corresponding corners; wherein the electrical connector system is configured such that when the male connector is urged into the coupling portion, the first electrode is urged towards the base of the female connector by the one or more biasing surfaces to form an electrical connection between the first electrode and the second electrode positioned between the base and the first end of the male connector; wherein the system is configured such that the first electrode is urged towards the base of the female connector in response to the first end of the male connector being inserted into the coupling portion at an angle to the base of the female connector and being rotated towards the base of the female connector; characterized in that: a distance between the coupling portion and the rear wall is substantially the same as a length of the male connector from the first end of the male connector to a second end of the male connector that is opposite to the first end.