LG 27BK85U-W: 27'' HDR10 IPS UHD 4K Monitor (3840x2160) with USB Type-C™, HDCP 2.2 Compatible, MAXXAUDIO, Acrline Stand & 3-Side Virtually Borderless Display | LG USA Business
L32p-30 31.5'' UHD USB Type C Monitor With LC50 WebCam
Amazon.com: 4K Portable Touch Monitor Travel Screen Second Touchscreen Extender UHD USB C Computer Gaming for Laptop 14.0 Inch 3840 X 2160 IPS Compatible with Mac,MacBook,Nintendo Switch : Electronics
27" E27k G5 USB-C 4K Monitor
Review: LG's USB-C-enabled 4K Monitor lends single cable simplicity to 12" MacBook owners, but not without some compromises - 9to5Mac
Dell S2722QC 27.0" 4K IPS LED UHD AMD FreeSync VESA Monitor (USB-C, HDMI) Platinum Silver S2722QC - Best Buy