... -DC12V/1A 3)Specifications:270*150*50mm 4)With pager quantity : 999pcs Wireless Calling Syestem An extemal power amplifier and the serial ... ation.Freely set up the length of receiving music.Each pager can set different chord music.Number display types can be ... number:3pcsWith pager quantity : 999pcs Letters show: A,B,C,D,E,F,H,P,J,L(80 in English) Wireless Calling Pager