These storage solutions are new form factors of the 850 EVO SSD that was announced last year and adopts Samsung's 3D V - NAND technology that ensures improved performance.
The S3700 has 264GiB of NAND on - board but only exposes 186GiB of it (200 GB advertised capacity) as user accessible storage, the rest is used as spare area to improve performance, consistency and endurance.