Material Environmentally friendly silicone material - The hand exerciser rings are made of premium silicone. suitable for smoosh. press. pull and pull without smell. without stains. without edges. noiseless. It will immediately return to its original shape 3 levels of resistance - Rose-3KG / 6.6LB: Easy Lake Blue-4KG/8.8LB: Medium Royal Blue-5KG/11LB: Difficult. Stressed work in different ways with several options. from advanced beginner. home or gym. Great for rehabilitation. fitness and relaxation - It can improve your finger strength and dexterity. more forearm musculature. It is therefore training for rehabilitation. longtime typists.Ideal for athletes (tennis. basketball. boxing. crossfit. golf and shooting) and musicians (guitarists. bassists. pianists and violinists). Easy to use and portable - Exercise your hand and forearm anywhere. whether you are home. at work. while walking. in the car or doing your favorite sport because the rings are light and easily portable. Sized for a perfect and comfortable fit - Sized specifically for adult hands. unlike other brands. to maximize the benefits of exercise and ensure a challenging yet safe experience. Ideal for strong men or women.