If you are interested in Massage Chairs I'm sure you've seen or heard of the term 2D, 3D and 4D. These terms are in reference to the Massage Chair Rollers. The rollers are the main source of massage other than the Airbag compression massage. Think of the rollers as the masseuses' hands.
In a 2D Massage Chair the rollers can move up and down, side to side. To adjust the intensity on a 2D Massage Chair you can adjust the speed of the rollers.
If your looking for a more human-like massage feel then a 3D Massage Chair is a great option. The rollers on a 3D Massage Chair moves up and down, side to side and also in and out. Many 3D Massage Chairs have manual modes to customize the specific area of the body you want to focus on. You can also adjust the intensity by telling it to push in hard for a more human-like massage.
For the highest rated luxury massage you can't go wrong with a 4D Massage Chair. A 4D Massage Roller moves up and down, side to side and in and out just like a 3D Massage Chair. The difference comes in the ability to vary the speed of motions just like human hands operate.