If it was a one gang box in the wall I would suggest a RACO #5403-0
weatherproof extension adapter with 3/4" hubs. I can't find a two gang
version in RACO, Steel city, or Pass & Seymour.

You could use a blank cover with a hole suitable for 3/4" however if it is a
metal cover, it must be grounded. Also the splices would have to be
accessible without the removal of the conduit, wires, fittings, etc. You
could accomplish this by using a nylon two gang blank cover with a gasket
and make your own hole in it using a hole saw or unibit and a slow drill.

You would come out of the cover with a 3/4" angle fitting and connect to a
short piece of 3/4" liquidtight flexible nonmetallic conduit. The other end
of the flex connects to your 3/4" pvc using a straight fitting and a pvc
female adapter. Using the flex allows the cover to be removed without
having to take anything apart. Just be sure to leave enough slack in your
conductors.


John Grabowski
http://www.mrelectrician.tv


"Dan" wrote in message
...
I am wiring a SPA and have a manufacturer supplied subpanel. The
contractor prewired my 230v connection to a flush, plastic, double gang
outlet box
with a plain metal cover on it. I need to run the wiring from the gang
box
to the subpanel using three quarter inch weatherproof plastic conduit. I
can't find an appropriate connection to attach the conduit to the face of
the gang box. I have some right angle and straight weatherproof fittings,
but I can't find an appropriate face plate to accept the fitting. I'm
thinking it would look like a plain faceplate with a three quarter inch
hole. What I have found is box covers that do not fit with half inch
holes
in them. Does what I am looking for exist? Am I thinking about the
connection correctly?
Thank you, Dan. Remove protection to reply.