The Pinpoint Trigger Ball from Fitness-Mad! Give your muscles a precise acupressure massage with the PinPoint Trigger Ball. Helps to release tight smaller muscle groups and "flush out" toxins which can build-up in the muscles. The blunt spikes provide acupressure release for you; feet, hands, shoulders, upper back, forearm, outer leg, glutes or hips. Ideal for use against a wall to target trigger points and tight muscles in the back, or any time your muscles feel tight! It may be small but it is mighty! Features Pinpoint Trigger Massage Ball. precise acupressure massage. Helps to release tight smaller muscle groups. Acupressure release for you; feet, hands, shoulders, upper back, forearm, outer leg, glutes or hips. 44mm diameter. PVC.