Magnifying Goggles

Of all the kit I bought to complete the Makerbuino, this the most useful. Sadly, they arrived yesterday, 2 days after completing the project.

Using them for reading books/phone - they are so good (for a soon-to-be-fifty year old with deteriorating eyesight.)

Weirdly, the 1.0 magnifier is the best one - why is this?