The UK's most common cap fitting, with a push and twist action. B22, or BC, is 22mm diameter and with two locating lugs. It is usually found in ceiling pendants.
A smaller version of the bayonet cap, with a push and twist action. B15, or SBC, has a 15mm diameter. Used in smaller decorative fittings, chandeliers and appliances.
Edison Screw (ES) or E27 is the UK's second most common cap fitting, featuring a screw-in connection with a 27mm diameter. Found in a vast range of applications.
A smaller version of the screw cap, with a screw-in connection. E14, or SES, has a 14mm diameter. Used in smaller decorative fittings, chandeliers and appliances.
GU4 Bulbs have two long pins with a 4mm distance between them. Found on low voltage lamps, they have a push fit action and come in Halogen or LED variants.
GU5.3 (MR16) Spotlight Bulbs have two short pins with a 5.3mm distance between the pins. They have a push fit action and come in Halogen or LED variants.
GU6.35 Spotlight Bulbs have two short pins with a 6.35mm distance between them. GU6.35 bulbs have a push fit action and come in either Halogen or LED variants.
GU10 Spotlight Bulbs have a similar looking fitting to bayonet cap, with two pins on the bottom, 10mm apart. GU10 Spotlight bulbs have a push, twist and lock action.
G4 Capsule two pin bulbs are commonly used in low voltage decorative light fittings and intricate light displays. They have a 4mm distance between the two pins.
GY6.35 Capsule two pin bulbs are commonly used in low voltage decorative light fittings and intricate light displays. They have a 6.35mm distance between the pins.
G9 Capsule bulbs are commonly used in low voltage decorative light fittings and intricate light displays, and have two looped metal prongs on the bottom, 9mm apart.
These linear double ended bulbs feature a white connector on each end, and are found in flood lights and security lighting. They usually measure 78mm or 118mm long.
The future of light technology, and the one we recommend as your first choice. Don't be put off by the upfront cost of LED light bulbs, they could save you hundreds in the long run. The most energy efficient bulb, LEDs use up to 90% less energy than a traditional incandescent, and can last up to 25 years. An LED bulb could save you more than £180 over its lifetime, and with instant full light as soon as you flick the switch, is the smart choice.
CFLs are cheap and widely available in most sizes and outputs. Older CFLs were slow to brighten, but this has improved considerably in recent years. CFLs use up to 80% less energy than incandescent bulbs and quickly pay for themselves in energy savings, but not everyone likes the light they emit. They have an average lifespan of 10 years.
Similar to incandescent light bulbs in colour and quality as it uses a tungsten filament, halogen bulbs also use the same amount of energy, making them significantly more expensive to run than other energy savers. With an average lifespan of just 2 years, a halogen bulb also emits a lot of heat, meaning it is unlikely to pay for itself before it fails.