The "Spray Off Mini" is a rain deflector that works with the ARRI LMB-6.
It's easy to handle and set up. Just insert it into the matte box instead of the first (front) filter tray.
The "Spray Off Micro" uses motors to rotate the glass so fast that water simply flies off the sides. Power is supplied from the camera with an RS-cable.
At least one filter tray remains for the parallel use.