A pneumatic sensorindicator device includes a sensor assembly having a bellows receiving chamber and sensor housing. In one preferred technique, an additional pass through server is added to connect end users to their associated SIP proxy server, and to connect a CTI applications computer to the system. In particular, the present invention is concerned with compounds of the general formula wherein R1 to R5, R5\u2032, X, Y and A are as defined in the specification. The MAL has a down-track thickness from 5 to 20 nm, a width equal to the track width in a cross-track direction, and extends 100 to 500 nm in a direction toward a back end of the main pole.