Trigger Point MB1 Massage Ball The Trigger Point MB1 massage ball is the perfect tool to release tightness in smaller muscle groups. Create the feel of a massage therapists compression with the MB1 on a hard surface. Apply direct pressure on areas like the pectorals, piriformis, psoas, glutes and lats to help alleviate soreness from training and competition. A compact size allows for easy travel in a carry-on or gym bag. A 2.6 Diameter for easy storage and travel. Isolate smaller, overworked muscles of the upper and lower body. The layered, multi-density construction helps break up adhesions and promote blood flow for healing of damaged muscle tissue.