Accessible Phone Charging for Businesses Let your guests charge at your place of business with the WM4. It's easy to mount on a wall and features a tray to hold phones while they wait for your service. Fast Charging Cables WM4 comes with four charging cables: 2x USB-C + 2x Apple Lightning, outputting 20 watts of PD power. Compact Size WM4 is a smaller version of the popular WM9, giving businesses with less wall-space an easier and lighter charging alternative.