A circuit breaker comprising: a single pole module of a circuit breaker comprising a first portion including a first current path region (250, 260, 270, 280) and first and second sections (103, 105) and second portion opposite the first portion including a second current path region (350, 360, 370, 380) and first, second, third and fourth sections (106, 107, 108, 109), the first and second portions (200, 300) being separated by an interior wall; a circuit board comprising a trip solenoid disposed within the first section of the first portion; a lever mechanism in operable communication with the trip solenoid and disposed within the second section of the first portion, the lever mechanism further comprising an end portion configured to be in operable communication with the trip solenoid and configured to be actuated by the trip solenoid upon a predetermined electrical condition; and a circuit protection device disposed in the first, second, third and fourth sections (106, 107, 108, 109) of the second portion and a tripping mechanism in operable communication with the circuit protection device and disposed within the third section of the second portion, wherein the lever mechanism is in operable communication with the tripping mechanism and configured to trip the circuit breaker; wherein the first and second sections (103, 105) of the first portion of the single pole module occupy substantially half of the single pole module and the first, second, third and fourth sections (106, 107, 108, 109) of the second portion of the single pole module occupy substantially half of the single pole module; wherein the second section of the first portion and the third and fourth sections (108, 109) of the second portion are disposed opposite each other; characterised in that the lever mechanism includes a pin on a side thereof extending through the interior wall, and the third section of the second portion further comprises an activator in operable communication with the pin of the lever mechanism and configured to move when the lever mechanism is actuated. a single pole module of a circuit breaker comprising a first portion including a first current path region (250, 260, 270, 280) and first and second sections (103, 105) and second portion opposite the first portion including a second current path region (350, 360, 370, 380) and first, second, third and fourth sections (106, 107, 108, 109), the first and second portions (200, 300) being separated by an interior wall; a circuit board comprising a trip solenoid disposed within the first section of the first portion; a lever mechanism in operable communication with the trip solenoid and disposed within the second section of the first portion, the lever mechanism further comprising an end portion configured to be in operable communication with the trip solenoid and configured to be actuated by the trip solenoid upon a predetermined electrical condition; and a circuit protection device disposed in the first, second, third and fourth sections (106, 107, 108, 109) of the second portion and a tripping mechanism in operable communication with the circuit protection device and disposed within the third section of the second portion, wherein the lever mechanism is in operable communication with the tripping mechanism and configured to trip the circuit breaker; wherein the first and second sections (103, 105) of the first portion of the single pole module occupy substantially half of the single pole module and the first, second, third and fourth sections (106, 107, 108, 109) of the second portion of the single pole module occupy substantially half of the single pole module; wherein the second section of the first portion and the third and fourth sections (108, 109) of the second portion are disposed opposite each other; characterised in that the lever mechanism includes a pin on a side thereof extending through the interior wall, and the third section of the second portion further comprises an activator in operable communication with the pin of the lever mechanism and configured to move when the lever mechanism is actuated.