The thunderbolt 3 (Usb-c) to thunderbolt 2 adapter permits you to connect thunderbolt and thunderbolt 2 devices — external exhausting drives and thunderbolt presentations.
The Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter permits you to connect Thunderbolt and Thunderbolt 2 devices such as external exhausting drives and Thunderbolt docks to any of the Thunderbolt 3 (USB-C) ports for your MacBook Professional.
As a bidirectional adapter, it could also connect new Thunderbolt 3 devices to a Mac with a Thunderbolt or Thunderbolt 2 port and macOS Sierra.
Note: This adapter supports Thunderbolt 2 devices and Thunderbolt presentations. It does NOT strengthen DisplayPort presentations just like the Apple LED Cinema Show or third-birthday party DisplayPort and Mini DisplayPort presentations.