This is a simple distant signal for use in front of home signals. The signal aspects change from Vr0 (yellow/yellow) to Vr1 (green/green). Track current can be controlled by means of the 72751 control box. Maintenance-free LEDs. Height without base approximately 61 mm / 2-3/8".A suitable control box is 72751. The 74380 signal cannot be operated with other controllers!