These are a bit of a hybrid of the Roller Fly and the Incline Dumbbell Fly, as they tend to hit from mid (sternal) to upper (clavicular) fibers of the pectorals.

Utilize the full range of motion; particularly get yourself into that full stretch, as the most recent studies have shown, the loaded stretch is one of the best, if not the best, positions to be in for muscle hypertrophy.