IsoFreeze PCR racks are manufactured with a gel-filled center section that has temperature-dependent color-change material, which changes from green to yellow or purple to pink. There is a dramatic change to a contrasting color at 7°C, so you can use this indicator to determine when the temperature of the rack, or even a single well, is rising to above standard refrigeration temperature. Each rack comes with an individual snap-on lid made of clear polypropylene. Also available in a new SBS footprint design, the new design provides a more compact option for crowded benchtops or freezers as well as conforming to robotic dimension standards for use in automation protocols.