Original VECTASTAIN® ABC KitGood sensitivity/low backgroundOriginal avidin/biotin ABC complex formulationLow costAvailable without (“Standard” kit) or with biotinylated species-specific secondary antibody.Kit Contents:3 ml normal horse serum1 ml biotinylated horse anti-mouse IgG secondary antibody2 ml each of concentrated A and B reagentsSufficient reagents to stain approximately 1000-2000 sections.