A deflectable sheath assembly comprising: a tubular shaft receiving first and second longitudinal movement wires (34, 36) operably coupled to a distal end thereof; a control handle having a main body configured to receive first and second bevel gears (24, 26) having teeth (42, 44) on a surface thereof, the first longitudinal movement wire operably coupled to the first bevel gear and the second longitudinal movement wire operably coupled to the second bevel gear; a rotatable adjustment knob operably engageable with the control handle, the rotatable adjustment knob having an external geared portion matingly engageable with the first and second bevel gears, the rotatable adjustment knob moveable at least between a first and a second position, wherein in rotation to the first position the rotatable adjustment knob engages the teeth of the first bevel gear and causes the first bevel gear to rotate in a direction that causes the first longitudinal pull wire to wrap around a surface of the first bevel gear to cause proximal longitudinal movement of the first longitudinal movement wire, and further wherein in the rotation to the first position the rotatable adjustment knob engages the teeth of the second bevel gear and causes the second bevel gear to rotate in a direction that causes the second longitudinal pull wire to unwrap around a surface of the second bevel gear and cause tension to be released on the second longitudinal movement wire, and further wherein in the rotation to the second position the rotatable adjustment knob engages the teeth of the second bevel gear and causes the second bevel gear to rotate in a direction that causes the second longitudinal pull wire to wrap around a surface of the second bevel gear and cause proximal longitudinal movement of the second longitudinal movement wire, and further wherein in the rotation to the second position the rotatable adjustment knob causes engagement of the teeth on the first bevel gear and cause the first bevel gear to rotate in a direction that causes the first longitudinal pull wire to unwrap around a surface of the first bevel gear and cause tension to be released on the first longitudinal movement wire. a tubular shaft receiving first and second longitudinal movement wires (34, 36) operably coupled to a distal end thereof; a control handle having a main body configured to receive first and second bevel gears (24, 26) having teeth (42, 44) on a surface thereof, the first longitudinal movement wire operably coupled to the first bevel gear and the second longitudinal movement wire operably coupled to the second bevel gear; a rotatable adjustment knob operably engageable with the control handle, the rotatable adjustment knob having an external geared portion matingly engageable with the first and second bevel gears, the rotatable adjustment knob moveable at least between a first and a second position, wherein in rotation to the first position the rotatable adjustment knob engages the teeth of the first bevel gear and causes the first bevel gear to rotate in a direction that causes the first longitudinal pull wire to wrap around a surface of the first bevel gear to cause proximal longitudinal movement of the first longitudinal movement wire, and further wherein in the rotation to the first position the rotatable adjustment knob engages the teeth of the second bevel gear and causes the second bevel gear to rotate in a direction that causes the second longitudinal pull wire to unwrap around a surface of the second bevel gear and cause tension to be released on the second longitudinal movement wire, and further wherein in the rotation to the second position the rotatable adjustment knob engages the teeth of the second bevel gear and causes the second bevel gear to rotate in a direction that causes the second longitudinal pull wire to wrap around a surface of the second bevel gear and cause proximal longitudinal movement of the second longitudinal movement wire, and further wherein in the rotation to the second position the rotatable adjustment knob causes engagement of the teeth on the first bevel gear and cause the first bevel gear to rotate in a direction that causes the first longitudinal pull wire to unwrap around a surface of the first bevel gear and cause tension to be released on the first longitudinal movement wire.