Compact fluorescents start at 10 watt & go up to 26 watts. From different manufacture they are known as Double Biax, Dulux D or DE, Lynx D, Twin tube with integral starter. The 2 pins have code "D" the 4 pins have "DE".
The 4 pins are high frequency and dimming operation.Suitable for use in emergency lighting products.
For use with external control gear. there is colour choice of warm white, white, daylight and cool white.
 
2D compact fluorescent horse shoe shape are available from uk lightbulbs, with wattage 10 watts, 16 watts, 21 watts, 28 watts, 38 watts, 55 watts.
They have 2 pin or 4 pin connection. there is colour choice of warm white, white,
 16 watt compact fluorescent 80% energy saving on a 100 watt standard incandescent bulb, compact fluorescent tube
 
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