Reed sensors can be selected for varying percentages of hysteresis. Generally a wide differential, one ideally used in liquid level sensing is about a 50% differential. For example, in a given application if the closure point is 1.0 inch (2.54 cm) from a given reference point, the drop-out point will be 0.5 inches (1.27 cm). Or Hysteresis = Dropout/Pull-in x (100%) = 0.5/1.0 x (100%) = 50%.