The ASUS MB169C+ USB Type-C Portable Monitor lets you carry around an extra screen when on the go without needing for bulk cables or AC power adapters. This ASUS monitor achieves this by taking advantage of USB Power Delivery to power the monitor from the computer and DisplayPort Alternate Mode technology, both of which run over a single USB Type-C to Type-C cable between the computer and monitor.
Fortunately, you can use the ASUS MB169C+ USB Type-C Portable Monitor with Apple's new line of Thunderbolt 3 Mac's like the Apple 15" MacBook Pro (Late 2016) which supports DispayPort 1.2 from their USB Type-C ports.
Once you connect the USB 3.1 Type-C to Type-C cable that comes with the ASUS MB169C+ USB Type-C Portable Monitor directly to any of the Thunderbolt 3 ports of the Apple 15" MacBook Pro (Late 2016), the monitor immediately lights up acting as a secondary display for the Mac.
The Mac shows that the highest resolution is 1920X1080@60hz (1080p) although you can change different resolutions from the Mac's Display settings.
Looking at the USB Power Delivery negotiation between the ASUS MB169C+ USB Type-C Portable Monitor and the Apple 15" MacBook Pro (Late 2016), we can see that the Mac offers 7.5 watts (5 volts @ 1.5 amps).
The monitor then accepts pulling 7.5 watts (5 volts @ 1.5 amps) from the Mac.
The Apple 15" MacBook Pro (Late 2016) again offers 7.5 watts (5 volts @ 1.5 amps) which again the monitor then accepts.
However, the ASUS MB169C+ USB Type-C Portable Monitor actually declared its power sink capabilities is 4.5 watts (5 volts @ .9 amps).
We can verify that the monitor is only drawing 4.5 watts which is incredible small for an external monitor. However, even at 4.5 watts, the Apple 15" MacBook Pro (Late 2016)'s battery will only last about 3 hours from fully charged to become fully depleted (assuming you don't have a separate AC adapter powering another Thunderbolt 3 port on the Mac).