And what that usually means is we have isolated that protein of interest because this band consists of a protein that has a specific type of mass, a specific type of size. Now let's owe and by the way, let's calculate what the yield in this case was. To calculate the yield, we follow this equation. So this divided by this gives us 85 divided by 200, which is 42.5 divided by 100 multiplied by 100, that gives us a percent of 42.5. Okay? So let's go back to this step.