The Able 2/Sho-Me 100 watt 4-function undercover siren has wail, yelp, phaser and air horn. It includes the wire assembly, remote center-off switch for wail and yelp functions, plus a center-off momentary switch for phaser and air horn sound. Dimension: amplifier - 2 3/8"H x 4 3/8"W x 5 3/8"D, switch - 2" H x 2"W x 1 3/4"D.