Isotherm Quick Freeze -70°C for 12 tubes from 0.5 to 2.0 ml. With alphanumeric ID code on the transparent lid and the lower section. For rapid and repeated refrigeration in the molecular biology laboratory. Can be used repeatedly for up to 45 minutes. Made of resistant polycarbonate filled with non-toxic insulating fluid. No direct contact between the tube and the insulating fluid. With non-slip feet.