Sizes and Fittings

Light bulb fittings are generally of 2 main types:-

1. Bayonet Fitting...... This is the traditional fitting used in the UK where the bulb is inserted into the holder and then rotated a quarter turn to lock into position
2. Edison Screw...... This is the fitting originating from continental Europe where the bulb is inserted into the holder and rotated until a good conection is made.

• Bulb types and sizes:- The codes for the most common types are:-
  E14:- This is a small electrical screw (SES) bulb often used for candles or smaller size bulbs. With a SES fitting bulb the outside thread diameter is approximately 14mm
  E27:- This is the larger size screw bulb known as the 'Edison Screw' bulb. With an ES fitting bulb the outside thread diameter is approximately 27mm
  B15:- This is a small bayonet fitting bulb often coded as SBC. With an SBC fitting bulb the bayonet diameter is approximately 15mm.
  B22:- This is a large bayonet fitting bulb often coded as BC. With a BC fitting bulb the bayonet diameter is approximately 22mm.