A method for generating digital events in response to inbound or outbound phone calls on analog phone systems is described. The level shifter may either couple or decouple input circuitry from a reference voltage in response to a firewall enable signal, may translate signal having a predetermined one of either a high or low state when the firewall enable signal is asserted. The transfer mechanism is configured to move the substrate between the first processing module and the second processing module. In another embodiment, the polymer includes nonionic, amphoteric, or anionic polymers. An upper jam portion is disposed on a top portion of the body member for tightly and smoothly receiving a hook type wiper member.