So let's take a look at the following four diagrams. So in diagram A of indirect Eliza, we coat the surface of the well with an antigen. But in this particular case, we coat the surface with the antibody that can bind to that specific antigen that we are testing for. So the antibody specific to the antigen that we're testing for is attached to the bottom of the well. And then we take our sample, for example, the blood sample, or it could be a urine sample, and we place it into our mixture. And if the antigen is present in that mixture, it will bind to our antibody that is coated on the surface of our well.