These are needed to connect two SSDs to my Mac Mini which is mounted behind my monitor. Perfect length as they provide access to SSDs without having to pull excessive slack. Just as effective as if my SSDs were directly attached. Highly recommended.
Pros
*NOTE* --- If you have connected a USB-C 2.0 peripheral to this USB-C 3.1 extension cable and it is not working properly, swap the connector and try again. This is due to a USB-C protocol compatibility issue and you need to connect a USB-C 2.0 peripheral to a USB-C 3.1 port in a specific direction.