Directed Electronics 479X Clifford Matrix Responder Transmitter 4-Button, 2-way Responder Remote Control DEI replacement for the Viper 561XV, 790XV, 791XV, 690XV, 691XV Python 880XP, 881XP, 680XP and 581XP Clifford Matrix RS III, RSX 3.5, 2.5X and RSX 1.5 Remote Features:LOCK, UNLOCK, AUX, PANIC Light:LCD Board:Two Way 433Mhz Replacement LCD Remote for Clifford RSX 3.5, 2 Way Pager Remote.