It carries 9 positions in a 2-row DE (E) shell size layout — the standard DB-9 footprint. The housing is free-hanging (in-line) with an unthreaded flange, so it mates into a receptacle without jack-screws; retention relies on the slide-lock or friction of the full mated pair.
This is a shell only — the spec note says Contacts Not Included. You order the male crimp terminals separately. For the AMPLIMITE HDP-20 series, that means the standard stamped-and-formed signal contacts.
Mating half and field fit
This plug mates with a standard D-sub receptacle housing — the female side that accepts socket contacts. Both halves use the same shell size (DE, E). Because the flange is unthreaded, the mating pair relies on the slide-lock mechanism or a simple friction fit.