This is a REAL Rick Baker artifact. It is a Cinovation life cast of the film's star, MICHAEL CLARK DUNCAN. On top of this life cast Cinovation added a foam rubber facial appliance that is the Gorilla General Attar. I believe that this was used early in preproduction while working out exactly how the screen used mask components would work and fit for Mr. Across the upper lip, you can see where someone made the lip thinner (I can guess that this was done to make acting through the make up easier).
There is still some casting, and rubber residue here and there. The left ear is missing, and the right ear is damaged. There are places where some of the foam is gone.
This is exactly as it was left by the film makers. I do not know if the facial appliance can be safely removed, but if you did, you would have a highly detailed bust of Mr. Duncan (you can even see his real teeth through the mouth). The helmet was restored several years ago.It started out as only the front half of a General Attar helmet. I do not know why the film makers cut it in half, but perhaps it was for close ups, so the whole helmet didn't interfere with the make up, but that is just a guess. The rear was restored using another Hieroglyph helmet (Attar's helmet was a Hieroglyph helmet with the cool ape crest on the front). So, while it is all real helmet parts, the paint is not original. The item "PLANET OF THE APES RICK BAKER MICHAEL CLARK DUNCAN ATTAR SET" is in sale since Monday, February 13, 2017. This item is in the category "Entertainment Memorabilia\Movie Memorabilia\Wardrobe\Originals". The seller is "realpropman" and is located in Blue Jay, California. This item can be shipped worldwide.