A trawl door, deflector, vane or paravane (40) constructed with adjustable panels (22, 23, 24) and driving units (25) for control the water flow through the spreading device during towing through the water with remote control where driving units (25) are used to adjust the position of the panels control the water flow through the spreading device and maneuver the spreading device in optimum position in the towing direction, horizontally or vertically, the panels are adjustable independently to give enhanced performance of the operating systems, fishing trawl or seismic survey system, without having to pull the system to the towing vessel to adjust manually.