What is the proper form for performing a seated rear delt fly exercise?

To perform a seated rear delt fly exercise, sit on a bench with your back straight and chest up. Hold dumbbells in each hand with palms facing each other. Keeping a slight bend in your elbows, raise your arms out to the sides until they are parallel to the floor. Squeeze your shoulder blades together at the top of the movement, then lower the weights back down with control. Repeat for the desired number of repetitions.