This is an SSD drive with a 500 GB storage capacity. The form factor is M.2, which is the most efficient form factor.
From Amazon
SanDisk Professional 500GB G-DRIVE PRO SSD, Ultra-Rugged Portable External NVMe SSD, Up to 2800MB/s, Thunderbolt 3 (40Gbps)
Clove Technology
SanDisk G-DRIVE PRO External solid state drive - 500 GB