3.5 Volt 0.2 Amp Screw Fit MES Vacuum Bulb

Vacuum bulbs are the basic type which are best for low power lighting where high intensity light is not required. They are the lowest cost, but because the filaments operate at a relatively low temperature, only a moderate light quality may be achieved. This can be a shortcoming in cycle headlamps and flashlights if a penetrating beam is required.