pressure positive co. the original knobble the pressure positive co. this all-wood massage tool is another traditional favorite of therapists and self care enthusiasts who prefer the look and feel of natural, turned wood. about the size of a large mushroom, the cap is held in the palm of the hand, and the smoothly rounded stem is used to apply pressure to trigger points in soft tissue. some gentle kneading motion with the knobble or slow movement of the part of the body being massaged may be helpful. bodyworkers often use the knobble to save wear and tear on their hands when working on tough spots. but the knobble is not meant to replace your healing hands, only to help them do more and last longer.