Disclosed is a return mechanism for elevator escape device. The porous tubular wall has a plurality of butterfly cells disposed in a direction orthogonal to the longitudinal axis of the tubular wall, each butterfly cell having two symmetrical wing portions, an abdomen portion, and an antenna portion. The method further includes ascertaining whether the second user is subscribed to the discretionary charging feature based on the receiving, and applying discretionary charging for determining call charges for the first user, based on the ascertaining. An enable clock generator generates a 1-period enable clock or a 2-period enable clock using a command signal generated for performing a predefined operation.