Biological indicators vials are easy to use and interpret with visual color readout in 24 hours (1261) or 480hours (1262/1264). Test packs present a challenge to the sterilization process equivalent to the AAMI recommended test packs. Each test pack contains a 3M Attestâ„¢ 1262 or 1264 Biological Indicator.- Indicator For Steam 270F/ 132C Gravity Displacement Steam Sterilizers, 24 Hour Readout, Blue Cap, 100/bx, 4 bx/cs (Continental US+HI Only) Stock Item