I am sorry if this is not the right place to post, but it is a real Colt lower, probably from the late 1970s / early 1980s in almost mint condition.
It is a full auto lower marked "COLT M16A1", serial 9xxx xxx. I think it was imported from old Malaysian Army surplus. It is dark grey, not black.
As some of you may know we are allowed to own full auto lowers here in Germany as the upper is the restricted part. Of course we are not allowed to use it with a working upper or installing fa parts in a semi rifle. So this is a collector's piece.
For me as a big Colt fan it is great to have as I cannot get my hands on a Colt made AR-15.
It has some stains on the right sight which are hardly visible on the photo, but can be clearly seen with the bare eye. I know, this is nit-picking. And i have heard advice like throwing it down the driveway, but please understand that this is a collector's piece I can't fire and take out with me.
I am not sure how to try to remove them without damaging the anodizing. Maybe someone has already tried thinner or something. What is the right method to clean the outer surface of anodized receiver parts?
By the way, if someone happens to have a spare hand guard cap (round Carbine type for .625 barrel), I would love to buy it as I am in desperate need for one and I cannot get it here. I have a friend in the US who is willing to receive it for me.
Greetings from Germany
Mike