2010 WTX3 Apeks Wing OPV and power inflator ( Dext: 1"165 against Dext normaly 1" )
Not sure what your point is.
The current Apeks single tank wing comes with the flat type dump valve that I posted I picture of.
To my knowledge, and it could be wrong, Apeks did not adopt the flat type dump valve on their buoyancy devices until they came out with the WTX-D series which I believe to be the 2014 model year. Aqualung had already been using this dump valve on select models of their BCDs as early as 2009 if not earlier.
-Z