Sensafe™ Low Range Peroxide Check is a break through in testing for Hydrogen Peroxide (H2O2). Utilizing ITS’ patented aperture technology, this strip allows for detection levels of 0.05, 0.3, 0.5, 1.0, 2.0, and 4.0 ppm, all in an easy dip and read procedure. Simply dip the patented aperture test strip into a 250ml (8 oz) water sample for 5 seconds with a constant back-and-forth motion, shake off the excess and view through the aperture to match to the closest colour.