Local Orderwire and Express Orderwire Item Description 4-Wire Level Sets the receive (Rx) and transmit (Tx) 4-wire orderwire level. 2-Wire Level Sets the Rx and Tx 2-wire orderwire level. Apply Applies changes made to the fields in the tab. Reset Cancels any changes to the tab and returns the fields to their last-saved settings. Help Displays context-sensitive help.