Maximum Overall Length (M.O.L.):
MOL is measured from the end of the lamp base to the top of the outer jacket.

Light Center Length (L.C.L.):
The distance from the light center to a specified reference point on the lamp.

Diameter:
The diameter is the maximum diameter of the glass bulb.

Maximum Overall Length (M.O.L.):
The distance between the ends of the bases.

Contact to Contact:
The length between contacts is the distance between the metal contacts which are recessed inside the ends of the bases.

Nominal Diameter:
The approximate diameter of the tube.