These manual freezing units are designed to be compact and user-friendly. Available in either a 20 straw capacity or 90 straw capacity they feature a high-quality styrofoam box, a stainless steel inner container, and a floating rack. The stainless steel container is filled with liquid nitrogen. During the initial cooling phase, the rack maintains the proper spacing between 0.5 ml or 0.25 ml straws while floating on the liquid nitrogen. After this phase, the straws are manually submerged into the nitrogen.
