Attach a rope attachment to the cable pulley of a lat pulldown station. Grab the ends of the rope attachment using a neutral grip (palms facing each other) and place one foot up on the knee pad post and lean back at about 45 degrees. Pull the rope towards your face as you spread the ends of the rope so that they end up on the sides of your neck just above your shoulders in the finish position. Your upper arms should be straight out to your sides with your elbows bent. Hold this position for a second as you squeeze your shoulder blades together contracting your rear delts and middle traps as hard as possible. Then slowly return the rope to the start position and repeat for reps. While this move somewhat mimics a cable row for the lats, because you are pulling the rope high to your shoulders, it places less focus on the lats and more focus on the rear delts and middle traps.
Putting your foot up on the knee pad post helps you to better stabilize yourself so that you can maximize the amount of weight you use for stimulating greater muscle growth of the rear delts and middle traps.