The Roll Down is a really useful back exercise. Whilst bringing mobility benefits from stretching out the hamstrings and back, it also works through your back muscles. This makes it a really useful exercise if you have any back pain in your daily life but do not find this exercise painful.
To set up for the Roll Down, begin on a raised box or platform with your shoulders back and weight hanging down (this can be a kettlebell, dumbbell or barbell - My preference is a kettlebell.) Slowly, you are then going to bring yourself all the way over so that you are leaning down with your head looking between your legs. It is important to go through his motion slowly, first bringing your chin to your chest and then going over one vertebrae at a time until you are as low as you can go. Come back up through the motion in the same way until you arrive back at the top with your shoulders back.
I would recommend not going for a particularly heavy weight due to the nature of this movement. It should feel really good as you are stretching out through both your hamstrings and your back. It is important to listen to your body throughout and stop if you feel any pain.