Manufactured with USP VI crystal class virgin polystyrene in a 100000 grade clean room. Treated surface. Flat base which is free from striation to maximize the usable growth area. Polyethylene cap available in two versions: blind standard cap for closed systems and vented cap with a 0,22 micron hydrophobic membrane to allow gas exchange minimizing the risk of cross contamination. Angled neck design to improve access of pipettes and cell scrapers. Engraved graduation on both sides and writing area next to the neck. Sterilized by gamma irradiation and certified free of DNase, RNase, pyrogens and cytotoxins. Packed in resealable bags. Certificate of sterilization included (to be downloaded free of charge here)