This repository contains four .vol files corresponding to four harp seal (Pagophilus groenlandicus) skull specimen scans from the Oslo Natural History Museum collections. The scans are centred around the maxilloturbinate mass. Scans performed by Øyvind Hammer using a Nikon Metrology XT H 225 ST CT scanner. .vol files found under scans.zip can be opened with Avizo or loaded directly from binary as a raw float[depth × height × width] array. Specimen Life stage CBL (mm) CBL* (/1) Collection location Collection year Collector Scan date Voxel scale (μm) Dimensions (vx³) 7357 Juvenile 148 0.71 Vardø, Norway 1897 March 2023 300 1440 × 1216 × 991 7498 Juvenile 163 0.78 March 2023 300 1440 × 1440 × 1440 7360 Juvenile 201 0.96 Vardø, Norway 1893 Dahl April 2023 300 1440 × 1440 × 1440 7495 Adult 209 1.00 Maniitsoq, Greenland 1893 Bistrup April 2022 127 1535 × 1855 × 1920