So this is a competitive binding assay and we use the antibody, because it's extremely sensitive to the structure of the hormone, and secondly, we put on it either a radioimmune tag, so it's an, it's a radioactive tag and that would then be called a radioimmunoassayune or, or an IA or we add something that has a fluorescent tag on it and then those are called ELI SA or these are fluorescent enzyme reactions. 