In article ,
JS writes:
I am newbie when it comes to lighting. I have not come across these
T lamp bulbs.

Is there a web page which show pictures or diagrams of the T lamps
(T5, T8, etc) so I can see how they differ from one another.

These are regular fluorescent tubes.
The number following the T is the diameter in 1/8ths of an inch.
(Some EU countries give the T-number in mm's instead, but not UK.)

--
Andrew Gabriel