Here is a pic that will help you get an idea on what sizes copperheads come in from FISH. The smallest is the #1, going up to the #5. We also make a #6 which is the same components as the number 5, but with no crimp in the middle of the head. This gives it a fatter body, much like the jump from the #3 to the #4. We do not make the dreaded "#0", as even in a lab it will only hold about 225lbs. When you hear about guys running out it out on a string of zeros, they are really on #1's 99.3% of the time.
Here is some more info about copperheads and rivet hangers from our catalog pages.