A “fork” attachment is better for any muscle region, such as the calf or hamstring muscle group. Rounded heads at times come in different measurements—Davé states gluteal muscles could fare greater with a medium or larger sized solution. Softer heads are appropriate for sensitive locations. Many thanks for signing up. https://allhealthmarket.com/product/therapy1/digital-tens-unit/tens-unit/tens-electrode-pads-large-thick-physiotherapy-conductive-gel-therapeutic-pressure-electrical-muscle-stimulator-massage-patches/