Main Line Signals Mainline Signal – 3 Aspect Click image to animate Mainline Signal 2 Aspect Click image to animate Mainline Signal Single Aspect (Red) Click image to animate Mainline 3 Aspect (Asia) Click image to enlarge Mainline Signal Tri-Colour Click image to animate Mainline Signal Bi Colour (Red Green) Click image to animate Mainline Signal Bi Colour (Yellow Red) Click image to animate Mainline Signal Bi Colour (Green Yellow) Click image to animate