Nest Scientific 3-layer tissue culture flasks are molded from crystal clear USP grade VI virgin polystyrene. 520cm^2 surface area equivalent to 3 X 175cm^2 flasks. Improve your CO2 incubator usage and handling efficiency by 5X using Nest multi-layer flasks. Flasks are plasma etched (TC treated) to support adherent cell lines. Flasks feature a vented cap with a USP grade VI 0.22uM PTFE membrane for gas exchange. Flask layers are ultrasonically welded together with no adhesives that may leach. Molded in an ISO 7 cleanroom, sterile (SAL 1 X 10^-6) and lot tested free of DNase, RNAase, DNA, cytoxins/endotoxins and BSE/TSE. Extensively tested for leachables/extractables per ISO 10993. cGMP compliant (21 CFR part 820/821). Extensive validation dossier available upon request.