High visibility 4mm multi-coloured LED (Red, Orange, Green, Blue, Purple and White). Dual step sensitivity, with top quality cone speaker. Built in I-Com transmitter technology for use with MX receiver with rubber ear inlays. Tru-run roller wheel and three position toggle switch. D-Tech Sensing System and silent start up. 1 x power out socket for use with illuminated bite indicators and supplied with hard case.