Stripped Upper - What is PD?

[OKCHunter]

I'm looking at an ad for a AR-15 stripped upper. It states "No PD / FA". I understand that FA is Forward Assist. What does PD stand for?

 

[adamsredlines]

Inquiring minds want to know...

 

[Glocktogo]

Port Door? Quite a few "slick side" uppers don't have provisions for mounting a port cover. Some don't have the case deflector for lefties either.

 

[adamsredlines]

Yep, thats it.
AKA its a slickside.

 

[D. Hargrove]

Best I can tell it means no Port Door Ejection Dust Cover or Forward assist.

 

[D. Hargrove]

ok, a little late, but.......

 

[OKCHunter]

Great. Thanks guys.