Ortho-Tolidine Presumptive Blood Test

Many investigators use this reagent as a confirmatory test after the Phenolphthalein Presumptive Blood Test.  Packaged in a plastic box with all the necessary premixed chemicals and supplies to conduct an O-Tolidine Blood Test.  The premixed liquid reagents are in plastic dropper bottles. 

A non-human known blood standard is included to monitor the results.