Packaged with 10 Negative Controls and 100 Tests / 10 NC. CSterilAmp II is a compact, self-contained biological indicator for monitoring industrial steam sterilization of liquids in small containers. SterilAmp II precisely integrates the process lethality. SterilAmp II contains a specially formulated culture medium that turns a dramatic yellow when spores grow. The SterilAmp II provides easy visual confirmation of sterilization within 48 hours, without the need for difficult and time-consuming laboratory work. 48 hour results; Small, conveniently-shaped ampoule ( 26mm x 6.5mm, 18mm size also available); Negative controls are included with each box of product; No laboratory required; Dramatic color change.