This product includes 480 ul of 10 x Buffer HT1, 405 ul of 10 x supercoiled plasmid DNA, 8 ul of 4500 x Dye H19 and 3000 ul of 10 x H19 dilution buffer. It is for 100 DNA relaxation assays in a 96-well plate format or 200 assays in a 384-well assay format. Human topo I enzyme in not included and can be purchased separately.