The TL159A by Black Box is an 8 port RS-232 RJ11 data broadcast device. Send async data to as many as eight printers, terminals, PCs, plotters, or other slave devices. All ports are DTE/DCE switch-selectable, and you can put one between your async CPU and up to eight terminals, students see everything on your screen. The TL159A is ideal for polling applications or other controlled environments.