They fit GU10 sockets, until recently occupied by 50W halogen bulbs. However, I've noticed an odd behaviour where the bulbs stay on after the light switch has been turned off.

Theatres will be forced to close and blockbuster West End shows will be put in jeopardy because of EU regulations that will force them to replace halogen spotlights, campaigners have warned.

Philips Hue smart bulb range, which lets you control your lights from your smartphone, has added a new GU10 spotlight to the range. The screw-in Hue lights will let you easily install the new ...