Lexar has made a name for itself in the portable storage market. They are very well known for their SD cards and USB sticks, so it's natural for them to expand into other areas of flash storage, like consumer SSDs. Lexar was founded as a subsidiary of Micron, but was sold to Longsys in 2017 and has been operating quite independently since.
The Lexar SL200 is a USB-C-based, portable SSD that uses the USB 3.1 interface with speeds of up to 500 MB/s. Traditionally, most large-capacity external storage has been based on hard drives, which come at very low cost per TB but have several drawbacks. First, since they are mechanical components, they are sensitive to shock—if you drop one, it's very likely broken. SSDs, on the other hand, are almost immune to external damage. Another plus of SSDs is that they don't use any mechanical components to transfer data, so their seek times are much lower than on HDDs, and transfer rates are higher, too.
Internally, the Lexar SL200 uses a Lexar DM918 controller paired with 3D TLC NAND flash and a USB-to-SATA bridge chip from ASMedia.