80 watt "industrial" laser beam diameter.

[Toymanf]

Hello all! I am gathering info on building my 24x48 cutting area laser. I am interested in using it for a significant amount of cutting. Can anyone offer me feedback or additional info regarding the beam diameter of the 80 watt "Industrial/longlife"(80mmx1120mm) tube. I asked "coletech" and received a reply of "6 to 7 mm" This seems quite large compared to the std (longer) 80 watt tube which is stated to be 3.5 mm.
I am sure this will be the first of many questions.
Thanks for any feedback
Frank