These are printed out of ASA which is a very durable, high heat resistant, and UV resistant polymer.
These are low profile and fit very snugly into your scope tube. They will not migrate out during recoil.
The very center portion has to be removed in a true 1x power scope or you’ll always see strange shadows in your line of sight.
Higher power scopes don’t have this issue. This ARD greatly reduces the chance of being spotted due to scope glare.
It also has the added benefit of acting as a sunshade and protects your lens from sticks, fingerprints etc.