AFE® 48 XT: 2D tubes with external threads in 48 SBS format. The advantage of the SBS format compared with conventional cryo tubes in the cryo rack, is the inbuilt compatibility with automated processes. The SBS rack makes a changeover to an automatic sample distributor easy. An advantage of the external thread: Depending on the application, the risks of cross-contamination can be minimised. Furthermore, there is no need to accept the disadvantages in terms of leak-tightness compared to the conventional solutions with internal threads due to the special, patented two-phase TPE compression. On the contrary, due to the two contact phases for the sealing of the liquid phase and a potential gas phase, this screw cap results in the very best sealing characteristics for safe, long-term sample storage.