This is a kit which allows you to finish assembling your stripped upper receiver. We sell them for standard 5.56 uppers as well as LR308 (DPMS Pattern) .308 uppers.
The kit comes with the following; dust cover door, dust cover spring, knurled dust cover rod (standard rod for .308 kit), forward assist, forward assist roll pin, forward assist spring.
The only part of this kit which is not "mil-spec" is the knurled dust cover rod. A "mil-spec" kit comes with a rod which requires a c-clip.
This c-clip seems to always get lost and is a pain to deal with and our knurled rod eliminates the trouble of losing a c-clip.
This is a superior kit and made in the USA