CPC (Circular Plastic Connector).

CPC's that use D-sub machined pins page 202 Allied series 20.
This pic is just something I found in a quick search and may not be representative of ones that use machined D-sub pins.
Interesting video from EAA on using circular plastic
connectors.
http://www.eaavideo.org/video.aspx?v=713328494001

Y11-02-21