Old-school lat isolation with a fixed arc.
Drive with the elbows and lats, not your hands. Feel the stretch at the top each rep.
With your shoulders aligned to the machine's pivot and your elbows on the pads, the fixed arc takes the lats through one of the longest ranges any back exercise offers, from a full overhead stretch to a hard contraction at your waist. Driving through the elbows removes grip and forearm strength from the equation, so the set ends when your lats do. The chest assists through the arc, but this is the rare machine that isolates the lats without a single rep of pulling with your hands.
It removes the arms and grip from the movement, so the lats fail on their own terms, while pulldowns train the whole pulling chain. Most backs benefit from both, the pullover for isolation, the pulldown for integrated strength.
Adjust it so your shoulder joints line up with the machine's pivot point. If the axis is off, the arc fights your anatomy and you will feel it in your shoulders instead of your lats.
The machine keeps constant tension through the whole arc and locks the path so the lats stay loaded. The dumbbell version is free and everywhere, but tension drops off badly at the top, the machine is simply the better lat isolator if you have access to one.
