Power Balls and Sensory Balls

Powerballs:
Powerballs, also known as gyroscopic hand trainers or gyroballs, are portable fitness devices used to train the hand and forearm muscles and improve grip strength. They consist of a spinning rotor held by a cord or handle. Moving the wrist causes the rotor to spin, creating a gyroscopic effect. A gyroscopic hand trainer works on the principle of centrifugal force. When the rotor is accelerated by rotating the wrist, a counteracting force is created, generating high resistance. The faster the rotor spins, the greater the resistance the hand muscles must overcome.  

How it works: The Powerball hand trainer consists of an inner rotor driven by a circular motion of the wrist. The rotation creates a moment of inertia, which generates additional resistance. The faster the rotor spins, the greater the resistance.
Grip strength: Training with a gyroscopic hand trainer strengthens grip strength. This can be particularly beneficial for sports such as climbing, tennis, golf, or weightlifting, where strong grip strength is required.
Forearm muscles: Using the hand trainer works the muscles of the forearm, including the wrist and forearm muscles. Regular training can lead to improved muscle strength and endurance.
Rehabilitation: Gyroscopic hand trainers are also used in rehabilitation to promote wrist mobility, blood circulation, and recovery after injuries or operations.
Coordination and dexterity: Training with a gyroscopic hand trainer requires good hand-eye coordination and fine motor skills. It can help improve the dexterity and precision of hand movements. 
Training effects: Powerball hand trainers are designed to strengthen the hand and forearm muscles, including the fingers, wrists, and forearms. Training with the Powerball can improve grip strength, grip force, and coordination. It can also be used in the rehabilitation of injuries such as carpal tunnel syndrome, tendonitis, or tennis elbow.
Training intensity: The intensity of training with the Powerball hand trainer can be increased or decreased by adjusting the speed of the wrist. The faster the wrist is moved, the greater the resistance and the more intense the training. The training can be individually adapted to abilities and needs.
Additional features: Powerball hand trainers often feature additional functions such as built-in LED lights that illuminate during training and can indicate speed. Some models also offer digital displays that show information such as speed, RPM, and training time.
Versatility: Powerball hand trainers can be used by people of various fitness levels and age groups. They are suitable for fitness enthusiasts, athletes, musicians, gamers, and anyone who wants to strengthen their hand and forearm muscles. 

Gyroscopic hand trainers are available in various designs and difficulty levels, from simple models for beginners to advanced models with higher resistance. It is important to follow the manufacturer's instructions and gradually increase the training intensity to avoid overexertion or injury. 

Haptic balls:
Haptic balls, also known as tactile balls, are balls with a special surface that provides tactile stimulation. They have different textures, bumps, grooves, or other surface structures designed to improve the sense of touch and sensory perception. Haptic balls are frequently used in rehabilitation, therapeutic training, or sensorimotor exercises to improve proprioception (awareness of body position), promote tactile sensitivity, and train hand-eye coordination. They can also be used for relaxation and to promote blood circulation in the hands. Haptic balls are available in various sizes, materials, and hardness levels to meet individual needs.