Materials: Stainless steel Three levels of weight selection: Spring 30kg adjustable force range 30-40kg Spring 40kg adjustable force range 40-50kg Spring 50kg adjustable force range 45-55kg Size: 65-68*18cm/25.59-26.77*7.08in Color: As shown in the figure Product features: 1. Square design, comfortable grip, suitable for grip strength training and hand circulation exercises. 2. Three adjustable levels of spring resistance, can choose appropriate intensity for training according to personal needs. 3. The adjustable spring design is suitable for different strength requirements, enhancing wrist, biceps, chest and other muscle exercises, and comprehensively improving muscle strength. 4. Lightweight and convenient, can be used anytime, anywhere, ideal for home fitness. 5. The multifunctional design can fully exercise your arm muscles through a variety of different movements and postures, allowing you to quickly improve your physical fitness level and shape a healthy body. Package includes: 1 pc Arm exerciser