These lamps are commonly found in downlighters, they are quite powerful low energy lamps with a very long life.

They need the correct lampholder and you cannot change from one wattage to the another you have to change the fitting.

The wrong lamp will not go into your fitting because they have plastic flanges which prevent this, if you have to force it it is wrong.

The wattage is written on the lamp and this and the colour tone number is all you need to know to order replacements.

downlighter tubes PL ecotone U tubes double turn