For our deep seat thwarts (sailing boats), the cushion is great with a double back section. To lean on normally, you just hold it on your back and can stretch your legs out on it. A cushion element (e.g. the one you sit on) could be a little longer for tall people, otherwise it would end up below half your thigh. The cushion is pleasantly heavy and does not easily blow off the boat (if necessary it floats!). There are many options - a selling point for us.