These runway side-lights use compact fluorescent which offer energy saving and long life as we use an 8000 hour lamp. The lamp we use can also handle a good voltage range and this combined with wiring mentioned below negates the need for expensive high voltage systems with constant current regulators as well as special installation and maintenance. These can be installed to operate off a dual 230V AC supply with alternate lights connected to different circuits so that a fault in one will not put the complete system out. Edison screw compact fluorescents are used and are easy to obtain. A protective guard has allen-keys for theft prevention. These also use CAA approved frangible couplings so that if they are hit, the lamp breaks off instead of pulling down the aircraft.