Immunohistochemistry (IHC) permits the visual identification of specific protein antigens in tissues for diagnostic purposes. Following application of the primary antibody, the presence of a target antigen is visualized by the sequential application of an enzyme-antibody conjugate that binds the primary antibody, and a chromogen reagent, to produce a colored reaction product that is visible by light microscopy. 3,3’- Diaminobenzidine (DAB) is a widely used chromogen for immunohistochemical staining with horseradish peroxidase (HRP) detection systems. In the presence of peroxidase enzyme, DAB produces a brown precipitate that is insoluble in alcohol and xylene. Val DAB Chromogen Kit contains two solutions: Val DAB Chromogen and the corresponding Val DAB Buffer. It is intended for use with an HRP detection system in an IHC staining procedure on the VALENT Automated Slide Staining Platform. The Val DAB Chromogen Kit is specifically formulated for on-rack mixing of Val DAB Chromogen and Val DAB Buffer, without the need for pre-mixing by the user. A mixing vial is required for each unique run of the VALENT.