An immense variety of replacement electric light bulbs awaits today’s buyers, from incandescent filaments to the latest low-consumption technology. E10 and E14 size light bulbs have varying power ratings, from small yet durable 15 watt oven, cooker hood and fridge bulbs upwards. E10 bulbs have narrow thread mountings, whereas E14 lamp bulbs are wide thread. In contrast, BA15d bayonet fitting bulbs are suitable for specialist lanterns and lighting signal towers on emergency vehicles. Neon lights are used as glowing orange indicators in instruments and appliances, or for novelty illuminations. Featuring bayonet fittings or dual wire connections, neon filaments also function as an integrated series resistor in electronic circuits, such as in oscillators or low-cost voltage and continuity testers. Alternatively, mercury vapour or metal halide gas discharge lamps give a warm, white colour tone and last longer than standard bulbs. Additionally, they produce a better light yield and can be used internally or externally, often in work areas and factory halls. Electricity consumption is around 35 to 60 watts, though ballast units may be required for some bulbs of this type. Mixed light lamps advertise 10,000 hours service and contain both a filament and a gas discharge tube. Finally, the indicator lamps category features various bayonet cap and screw base light bulbs.