A method is provided for treating at least a portion of a well. The pin tower has an opening therein configured to receive a pin therein along a pin axis. Consequently, audible artifacts, such as click-and-pop artifacts, can be reduced or eliminated. Good electrical contact at both ends of the slideable contact element is assured. In accordance with the electro-optical device having such a shading film, it is possible to reduce or prevent coating defects in an alignment layer, nonuniform rubbing treatment to the alignment layer, and cracking of a counter electrode due to the steps in the upper layers resulting from the formation of the shading film. Each switching element comprises a detent spring having a central detent and being captive within the chamber, and a detent roller mounted on the inner ring.