To add: for a visual difference for the A-D vs E/F models, the first thing is the SIZE. but this can be difficult to tell unless side by side. (the superbug is much bigger) The easiest way to determine (quick glance) is to look at the intakes (as mentioned by lieutfunaki) . The A-D models have round...

Just a quick thanks to all the VTB's for allowing the AFVTB's to visit your practice last night. We were unable to spectate, but the comms were most useful and educational. We look forward to the future, and appreciate all the assistance. Thanks again!

RR