... (4:3) Infrared interactive Whiteboard Appearance Metal nano,high gain, can write by whiteboard marker and dry erase.Touch square1543mm(width) ... opaque object, normal Whiteboard penu HCI-103(16:9) Infrared interactive Whiteboard Appearance Metal nano,high gain, can write by ... opaque object, normal Whiteboard penu HCI-112(16:9) Infrared interactive Whiteboard Appearance Metal nano,high gain, can write by ...