What Base Is My Light Bulb
Light bulbs come in many bases to fit different light fittings. The common types of light bulb can be broken down in to groups of bases and are shown here:
Bayonet Cap Bases
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Small Bayonet Cap |
Bayonet Cap |
SBC - B15 |
BC - B22 |
15mm Base Diameter |
22mm Base Diameter |
Screw Cap Bases
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Small Eddison Screw Cap |
Eddison Screw Cap |
SES - E14 |
ES - E27 |
14mm Base Diameter |
27mm Base Diameter |
Pin Bases
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GU5.3 Cap |
GU4 |
GU9 |
GU10 Cap |
MR16 LV reflectors |
MR11 LV Reflectors |
Capsule lamps |
50mm 230v reflectors |
Bi pin – 5.3mm between centre of pins. Pin dia 1.45-1.6mm |
Bi pin – 4mm between centre of pins |
Bi pin – 9mm between centre of pins |
Bi pin – 10mm between centre of pins.
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G4 |
G9 |
G53 |
GX53 |
Capsule lamps |
Capsule lamps |
AR111 Reflectors |
GX53 Cabinet lighting |
Bi pin – 4mm between centre of pins |
Bi pin – 9mm between centre of pins |
Bi pin – 53mm between centre of pins |
Bi pin – 53mm between centre of pins |
Bases For Tubular Lamps
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R7S |
G5 |
G13 |
G13 |
Previously halogen, now LED |
Previously T5 fluorescent, LED equivalent |
Previously T8 fluorescent, LED equivalent |
Previously T12 fluorescent |
78mm and 117mm long |
5mm between centre of pins |
13mm between centre of pins on 25mm tube |
13mm between centre of pins on 38mm tube |
Bases For Strip Lights
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S15S |
Found on tubular striplights |
15mm diameter base4 |
Compact Fluorescent
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Have a look in the bulb section of the website to see what types are available and feel free to contact us if you would like more information.
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