Weaver Modular Level System, Magnetic

Simple to use.

A little high priced for the material it is mad from. But, still would give it five stars for convenience.

This may sound a little corny, but after reading the reviews about this item and the Hawk Sport Optics Bubble Level, I bought them both and used them in conjunction with each other. Here is what I did. I leveled the gun rest with a torpedo level . I then attached the Hawk level to the rifle and lever it. I then placed one of the magnetic levels on the top turret of the scope and made sure the two levels read the same. As I snugged up the mount I would keep and eye on the two levels and glance into the scope from time to time until scope was snug. It really is a lot quicker than it sounds. I never had to keep backing off screws and starting over.

The fact that you can change the mounting attitude by moving the magnetic base.

maybe include two magnetic bases instead of one.

Does the trick. Worked flawlessly, just what I was looking for.

These are quality, well-made levels. Both are about 2" long. The one with the magnet is about 3/4" high and the other is about 1/2" high.

Illustrations of their use in typical mounting situations would have been much appreciated.

Suspect achieving a "perfect" vertical for the gun and scope is much more critical in longer range weapons than for the typical air gun, but what do I know?!

Nice, quality-made levels. Both are about 2" long and the one with the magnet is about 3/4" high, while the one without the magnet is about 1/2".

Since I have no experience with using them, would have appreciated some illustrations of use in typical scope mounting situations.

I suspect that achieving "perfect" leveling of the scope on the gun is more critical in longer range weapons than typical airguns, but what do I know!

Easier than trying to balance my 3 foot long bubbles on the rifle!

Nothing

Don't assume that the magnets will stick to something. They don't stick to aluminum! The only thing in my rifle in the breech area that is metal is the cocking lever! So, I just rest on in top of the breech which is perfectly flat.

Seems to work well, whatever issues have to do with the scope mounts rather than this item. In other words, these make alignment easy, the mounts, upon tightening, make maintaining the alignment much more difficult. Obviously, not Weavers fault.

I'd use bigger/more powerful magnets, perhaps different shapes.

This is a cranky, pissy procedure no matter what equipment you're using to do it or what you're using it on.
The Weaver product seems to work, at the very least, as good as, or better than anything else. Choosing this item appealed to me because the mountings allowed alternate applications. (The world is full of objects that require leveling, but not necessarily scope mounts. Think refrigerator, pumps, misc artillery, certain concrete projects, safes, etc.)
(Thought for the day: Artillery's first requirement is "LEVEL." Anything less is just throwing rocks at the blue-painted picts.