SILENCIO Power Muscular Professionals Ergonomic Wrist Exerciser & Hand Exerciser Home Workout - Ideal for Athletes, Sportsmen, Fitness Enthusiasts:Specifications:Color: blackSize:10*5.5 inches(L*H)Material: high quality AB plastic and springApplies to: outdoor, fitness, exerciseFeatures:This hand grip exerciser is lightweight, easy to carry.Perfect for strength training, flexibility and balance in conjunction with various workout programs.Help you to improve the resilience of motion.The pull handle can be adjusted by different size of hands and arm.Compact size, easy to take on the go, to the gym, office or use at home.Note:Please exercise evenly, not excessively, to prevent the plastic handle rupture and prevent your muscle strain.