Ya, that's probably off an atlas six.
They are a zamak gear with a 1/2" bore with two keyways, and stack on a
babbitt bushing with a 3/8" bore.

Paul K. Dickman

How do you tell between 6" gears and those for a 10-12"? I know the larger
lathes came with more, but are the gears different?

Wayne: How many were in this set?

GTO(John)