Samsung MZFLV256HCHP-000MV - 256GB M.2 PCIe NVMe 2280 MLC 3D-Nand SSD Solid State - CPU Medics
The 128GB Surface Pro 4 models use perhaps the worst NVMe based SSD in production (link is closest model on Samsung's site, but specs line up with benchmarks) : r/Surface
SAMSUNG 970 PRO M.2 2280 512GB PCIe Gen 3.0 x4, NVMe 1.3 V-NAND 2-bit MLC Internal Solid State Drive (SSD) MZ-V7P512E - Newegg.com