So I picked up a Colt Mark IV Series 80 on a trade yesterday. I did a serial search but as with most of their stuff nothing came back..... The previous owner said it was mid 90's ok, no big deal. I'm running into a couple small issues with features it has. Pics will be below to show but it has the flat top slide, skeletonized hammer, plastic trigger, extended beaver tail and is enahnced single piece grips..... what I'm confused about is the slide and barrel are ported....... I can't find this on any other 1911/1991 from this period. See pics Update looks to be an enhanced model based on the E suffix. The ports are what are getting me.