seniorgeezer wrote:
If you look at a long level there are usually two "bubbles", side by
side ... one concave up and the other concave down. I have always read
the one that is concave up in any application. No one at Home Depot or
Lowes home improvement stores seems to know the difference. Would you
please explain the difference, and which to use?

Thanks for your input,

Bob Burkett


The two bubbles are for convenience. Use the one with the concave down
for the position you are holding the level. You would use one if
leveling something on the floor, the other if holding the level against
something overhead.

Harry K