Mfr# 73-OPA28B
McKesson OPA/28 Test Strips. To verify the efficacy of McKesson OPA/28 Solution, user should test for the minimum effective concentration (MEC) prior to each use. 3 second dip time, read at 90 seconds. Large, easy-to-read indicator pad. Definitive color identification comparison chart on each bottle. 18-month shelf life (unopened bottle), 6-month shelf life from date of opening. Not Made With Natural Rubber Latex.