An end-sensing sensor assembly for proximity sensing including one or more sensing devices positioned between two axially magnetized ring magnets having like poles facing one another such that the magnetic fields emanating from the two axially magnetized ring magnets define a moveable balanced zone therebetween. The one or more sensing devices may be positioned within the balanced zone or outside the balanced zone, or combinations thereof. The balanced zone shifts in response to the approach of a magnetic, permeable, and/or ferrous material which cause the sensing device to actuate in response to a sufficient shift in the balanced zone. Upon removal or departure of the magnetic, permeable, and/or ferrous material, the balance zone shifts back to the initial position prior to the approach of the magnetic, permeable, and/or ferrous material.