Patented technology: Detects incorrect contractions and alerts you at the start of every workout. App: Set reminders and goals in the app while also tracking your progress on each exercise and LV score. Body-safe: Sealed with medical-grade silicone and 100% waterproof. Custom-fit: We?re not all built the same. That?s where the Optional Cover comes in. Rechargeable and portable: Our Carry Case doubles as a wireless charger. Nice. Six exercises: Strength, Speed, Lift, Pulse, Hold, and Step exercises help build muscle power, agility, and endurance. Four levels: Training, Beginner, Intermediate, Advanced.