The primary use of the VideoRay Pro 4 crawler attachment is for ship hull inspections in high currents, though it can be helpful anywhere you need to inspect a flat surface in rapid currents.
For many years VideoRay users have followed hard smooth surfaces by rubbing along them. In many cases, under ships, the technique involved rubbing the float block on the hull as the vehicle skirted beneath the ship. The VideoRay crawler allows this technique to be used smoothly, and extended to horizontal surfaces after the vehicle is attached. The suction created by the vertical thruster allows smooth, easy hull inspections in four knots of current or more. The simplicity, effectiveness, and utility of this accessory is amazing