Anodized aluminum block with 12 bore holes that accommodate 1.7 ml microcentrifuge tubes. Holder may be placed on any flat freeze drying surface such as inside Clear Chambers, Heated Drying Chambers or the built-in vacuum drying chamber of FreeZone Console Systems; or on FreeZone Stoppering or Bulk Tray Dryer Shelves, Product Shelves or Heated Product Shelves. One each. Microcentrifuge tubes are not included.