On the side opposite of the cathode plane is a set of anode wire planes set at potentials much higher (less negative) than that of the cathode. Each plane is separated from its neighbors by a small gap, usually on the order of 1 cm. A plane consists of many parallel conducting wires spaced by a few millimeters, and the angle at which the wires are oriented relative to the vertical varies from plane to plane. Together, these planes read out signals from the drift electrons. For a detector with "N" anode wire planes, the inner "N" − 1 planes are called induction planes. These are set at lower (more negative) potentials than the outer plane, allowing drift electrons to pass through them, inducing signals that are used for event reconstruction. The outer plane is called the collection plane because the drift electrons are collected on these wires, producing additional signals. Having multiple planes with different wire orientations permits two-dimensional event reconstruction, while the third dimension is found from electron drift times.