Be sure that hole is free of burrs and panel surface around hole is smooth and free of debris.
Using the hex portion on the body (not the sealing nut), screw the fitting tightly into the threaded mounting hole.
Insert the cable through the fitting to the desired position.
Hand-tighten the SEALING nut as far as possible. Hold the BODY hex stationary with a wrench. Using a second wrench, tighten the SEALING nut until the wire is securely held in place.
Using a wrench on the BODY hex, check to make sure the fitting is still screwed tightly into the panel.
To disassemble for cable replacement, use a wrench to hold the BODY hex stationary and loosen the SEALING nut with a second wrench. Grip the disconnected cable and pull while turning the cable in the counter-clockwise direction.