I didn't get the unit down it's in the Attic of the garage but got a copy of the manual in my filing cabinet , looked at it but gave no measurement's, the jet is a tube with groves for the hose on one end the other is pointed with a jet hole on each side to
discharge into both pri. vent.
If you will give me your E-mail add. or I will send you mine
and I can send you a nice large copy