I really love this knobbler. In a massage, using thumbs with hard pressure in certain areas, like either side of the spine is an important stroke, as is working on the 'knots' around the shoulder blades, and if your thumbs are not very strong, this is where the knobbler comes into its own. It fits beautifully into the palms so its easy to press and slide along; I like the two larger spheres and the smaller ones too which give a different feel. I use it for about 15 mins of the massage. The best thing is the smooth way it glides, friction free once massage oil has been applied. I think the slidey nature of it as well as the colour and the price are all perfect. I keep mine on the radiator when massaging, so it is already nice and warm for extra scrumptiousness! I recommend this product as it provides different, interesting sensations when used as well as being very efficient at getting the knots out of tense muscles.