T9 Fluorescent Circular Tubes – FAQs
What are T9 circular tubes?
T9s are circular tubes with a diameter of just over an inch (9/8ths of an inch). You can get circular tubes in other diameters such as T5 or T6.
What diameter are they?
T9 Tubes are around 28mm in diameter.
How are they fitted?
To fit T9s, you simply push the pins in to the lamp holder.