App-controlled belt for the abdomen and back. The Compex CoreBelt 1.0 offers two programs and allows you to train your abdominal muscles and lower back simultaneously to improve core stability. The app-controlled muscle stimulation for the abdominal and back muscles helps you tighten and strengthen your core stability. The Compex CoreBelt 1.0 utilizes EMS technology (Electrical Muscle Stimulation) to mimic natural muscle contractions during regular physical activity, resulting in stronger, firmer, and more defined muscles. Comfortable abdominal and back muscle trainer with an ergonomic design. Size S/M: waist circumference 65-85 cm.