Spectrum Chemical manufactures and distributes fine chemicals with quality you can count on including those with CAS number 612-82-8, Whether you call it o-Tolidine Dihydrochloride or 3 -3-Dimethyl-(1 -1-biphenyl)-4 -4-diamine Dihydrochloride you can be assured the products offered by Spectrum, meet or exceed the grade requirements or specifications for each individual product.