There’s no scientific way to ever level a scope to a rifle — at least not to any rifle that has ever been made.The bubble level is a wonderful tool but not for leveling scopes! It’s for leveling shooters in the field. Once the bubble is level, you know the scope is aligned the same as when it was sighted in on the bench (as long as the bubble was level at that time).
Many scopes are either waterproof, fogproof or both. But what it's mean, do you really need a waterproof scope and how to prove a scope waterproof and fogproof ?
The PP2-0104 is a 2 MOA LED red dot. On top of that the PP2-0104 has a built in solar panel for dual power options. This is similar to the Holosun HS503C.