Hammerhead decided to keep the industrial design clean and the options for external power easier. The Karoo is IP67 Water resistant and does not mandatorily need a rubber plug over the USB port. We specified a waterproof and dust-proof USB port that is similar to those found in high-end waterproof smartphones.
We also provide 2 Micro-USB Rubber Plugs in the box for saving you time with cleaning the port after muddy rides.
See the waterproof capability of the USB Port: