CGC books may have Newton Rings. These are very common with CGC books, If you are unsure what these are a quick internet search will explain.
The item "Amazing Spider-man #212 CGC 9.8 NM/MT 1st Hydro Man White pages 1981" is in sale since Wednesday, August 14, 2019. This item is in the category "Collectibles\Comics\Bronze Age (1970-83)\Superhero\Spider-Man". The seller is "stevenboutin" and is located in Pepperell, Massachusetts. This item can be shipped worldwide.