This exercise is great to work your triceps. At home, we use the resistance bands instead the cable machine.
Stand facing the cable machine. Position the cable attachment at a height above your head. Facing the bar attachment, grab it with the palms facing up (supinated grip) at shoulder width.
With your feet hip-width apart, brace your abs to stabilize your spine. Keep your torso aligned and pull your shoulder blades back and down.
Exhale and straighten your elbows, pressing the handle/rope down toward the floor in a slow and controlled manner.
Continue pressing until your elbows are straight but not locked. Pause briefly.