Research says:

  1. DQG AAA—–58.5mm
  2. Olight i3E EOS—–60.5mm

I do not own any DQG flashlights. Those 2mm cost $30-$40 more when compared to the i3E price. I still need to buy a titanium flashlight. I just can not make my mind up between DQG/Lumintop/Thrunite.

Good advice from Jerommel !