The Dense Storage system for low-temperature storage of biological samples and solutions combines 1 mL Nunc CryoBank tubes with the new 13 x 13 tube dividers and Nunc CryoBoxes. Many laboratories store samples as aliquots of 1 mL or less in 2 mL tubes. By using 1 mL Nunc CryoBank tubes and Nunc CryoBoxes with tube dividers, users can double their freezer capacity without taking up more lab space. Standalone tube separators can also be retrofitted to existing CryoBoxes for additional flexibility. Optional 2-D barcodes on the Nunc CryoBank tubes enable precise tracking and traceability. To facilitate manual handling, the CryoBank Picker Pen has been designed to fit into the top of each tube to uncap or move it between racks. It also doubles as a ballpoint pen.