Request a Free Energy Audit

What does the "8" in T8 mean?

The number 8 indicates that the tube diameter is 8 one-eight inches, meaning that this tube has a 1 inch diameter.

A T12 tube has a diameter of  12/8, that is, 1.5 inch and a T5 tube is a very narrow tube with a diameter of just 5/8 inch.

Examples of T12, T8 and T5 lighting:

Return to FAQ