Torque-Ball hand exerciser upgraded built-in pretensioner, eliminating the need for a starter cord for easier use. then rotate your wrist so the core spins at high speed, generating strong centrifugal force and progressive resistance to train fingers, wrists and forearms. LCD counter with real-time progress tracking lets you monitor every workout session clearly. The self-powered digital display shows RPM, power, time and estimated energy expenditure without batteries, so you can accurately evaluate your grip strength, endurance and improvement over time. The lightweight, compact wrist power gyro hand exerciser can be used in short 5-minute sessions with no complicated buttons or settings, making it perfect for home, office, travel or warm-up before sports. Portable and stress-relieving, the wrist gyro ball includes a convenient storage box and lanyard for safe transport and quick access. Its compact profile easily fits in your pocket, gym bag or desk drawer, allowing you to relieve stress, stay active during breaks, and perform quick, low-impact wrist exercises anytime without bulky equipment. Color: Black Material: plastic Package Contents: 1*Torque Ball with Counter