The light installation Colour by Numbers lights up the top ten floors of the tower. The floors have a window in each point of the compass and behind each window is a LED-lamp comprised of 36 light diodes in the colours red, green and blue. By mixing these colours, new ones are created. The light is evened out by a diffusing film attached to the lamps and windows.

Anyone can control the lamps with their touch-tone telephone. The system for the telephone control sits in the tower and is made up of electronics connected to a cell phone. The electronics answer incoming calls and give instructions to the user, who communicates with the system by pressing numbers. The system then controls the lamps via DMX.

The technology for the telephone control of the lights was developed by Neeme Nemvalts, Netz Mobile Control.