Cryovials are specialist tubes designed for ultra-low temperature storage of biological samples such as sperm, embryos, blood, and cell cultures. They are made from cryogenic-grade polypropylene or PETG, which resists cracking at liquid nitrogen temperatures. Cryovials typically feature leak-proof caps, colour-coding for sample identification, and barcoding options to improve traceability. They are essential for long-term sample preservation in IVF, veterinary, and research laboratories.