The High Security Straws from Cryo Bio System (commonly referred to as “CBS^TM straws”) are made from an ionomeric resin which has a number of significant advantages over PETG. They are sealed by thermal soldering using a special heat sealing device, the SYMS, from Cryo Bio System. Only using this device (or the automated MAPI or PACE instruments) can they be sealed properly, with a seal guaranteed according to published specifications.