Hey all,
May sound like a stupid question here, but are all ejection port covers the same in regards to A1/A2 etc?  I'm building a KISS rifle on an A1 upper and I need to buy the port cover assembly.  Will any one do?  Also, is there any reason to not go with a non-Colt part?  I'm using Colt parts on most of upper assembly, but I figured this isn't exaclty a "high stress" area so would DPMS, Delton, J&T, etc. be ok?

They are all standard for 5.56 then theres 9mm ones and ones that came on earlier model M16s..but pretty much everyone who sells parts will carry the standard port door assembly.

All the 5.56 covers are interchangeable.  There are three variations.  There's a sticky in the retro area with pics.