The Aquaflex Ultrasound Gel Pads come in a box of six. Each measures 2cm x 9cm (0.78″ x 3.5″). The Gel Pad is an aqueous, flexible, reusable, standoff for use with the HF54+ Hands-Free Therapeutic Ultrasound or other therapeutic or diagnostic units. This reusable standoff coupling agent is used with the HF54 Hands-Free Ultrasound applicator to contour to the patient’s body during therapeutic ultrasound treatment. The Gel Pads lasts 2-3 weeks when properly hydrated after each use.