These polypropylene containers are carefully engineered for the storage of histology specimens. The patented "O-Ring" polyethylene screw cap forms a seal that eliminates most formalin leakage and evaporation. The durable polypropylene container (5ml-1 liter) is translucent, flexible, resists cracking and splitting, and eliminates the problems associated with formalin evaporation. Histoplex™ containers are available in a range of sizes. The 40ml-1 liter sizes have graduations for easy fill line viewing. The 2-8 liter containers are opaque polypropylene with unique tamper evident snap-on lids.