Technical details of SSD's are used in Dec 2020 MBP 16" Release

Technically its not an SSD! It’s just a collection of Flash chips like what your phone uses. The controller is part of the T2 chip.

Review this MacBook Pro 16" 2019 Teardown Step 8.

Apple hasn’t altered the design with the 2020 model. Popping off your bottom cover You can double check things by reading off the chip markings compare them to what the teardown lists or search the web. Keep in mind Toshiba offered different sized parts to Apple so depending on what your system is the markings might be a different one.