The usb3c vgacab wpd is a usb c to vga adapter dp alt mode with a usb c charging port it is designed to transmit signals from usb c computers to vga monitors so that you can watch videos or slideshows on the big screen it also features a usb c female port so you can charge the host computer and supply power for the adapter simultaneously it can work on macbooks or googles new chromebook pixel as well as other usb c supported devices