STEAM BIOLOGICAL INDICATORSAXIS self-contained Steam biological indicators designed for monitoring the efficacy of 121°C, 132°C,134°C and 135°C steam sterilization cycles. It is easy to use; no sophisticated laboratory testing or analysis is required. The biological indicator contains Geobacillus stearothermophilus ATCC 7953 bacterial spores on a filter paper carrier packaged within a plastic tube and a cap. Inside the tube, there is a sealed-glass ampoule of specially-formulated culture medium containing a color indicator that changes color when spores grow. Chemical Indicator on the label provides an instant indication of exposure.24hr-3hr-1hr-30min and 20min options.The expiration date of 2 years from the date of manufacturingUse in conjunction with Axis AXRD-100 Rapid and AXDL-100 Dual Incubator